54020 Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 

1See U.S. Department of Transportation, ‘‘Action 

Plan to Reduce Motorcycle Fatalities,’’ at 8 (October 

DEPARTMENT OF TRANSPORTATION 

National Highway Traffic Safety 

Administration 

49 CFR Part 571 

[Docket No. NHTSA–2008–0150] 

RIN 2127–AK16 

Federal Motor Vehicle Safety 

Standards; Motorcycle Brake Systems 

AGENCY: National Highway Traffic 

Safety Administration, Department of 

Transportation (NHTSA). 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: We are proposing to amend 

the Federal motor vehicle safety 

standard on motorcycle brake systems, 

in order to add and update requirements 

and test procedures and to harmonize 

with a global technical regulation for 

motorcycle brakes. If adopted, today’s 

proposal would specify an additional 

dry brake test procedure to test each 

service brake control individually and 

with the motorcycle in the fully loaded 

condition, provide a new test procedure 

for assessing performance of motorcycle 

brakes from high speeds, provide a new 

wet brake test that better simulates inservice conditions, provide an improved 

test procedure for evaluating heat fade, 

add test procedures and performance 

requirements for antilock brake systems, 

if fitted, and add a power-assisted 

braking system failure test, if equipped. 

DATES: Comment closing date: You 

should submit your comments early 

enough to ensure that Document 

Management receives them not later 

than November 17, 2008. 

ADDRESSES: You may submit comments, 

identified by the docket number in the 

heading of this document, by any of the 

following methods: 

• Federal eRulemaking Portal: Go to 

http://www.regulations.gov. Follow the 

online instructions for submitting 

comments. 

• Mail: Docket Management Facility, 

U.S. Department of Transportation, 1200 

New Jersey Avenue, SE., West Building 

Ground Floor, Room W12–140, 

Washington, DC 20590–0001. 

• Hand Delivery: 1200 New Jersey 

Avenue, SE., West Building Ground 

Floor, Room W12–140, between 9 a.m. 

and 5 p.m. ET, Monday through Friday, 

except Federal holidays. 

• Fax: 202–493–2251. 

Instructions: All submissions must 

include the agency name and docket 

number or Regulatory Identification 

Number (RIN) for this rulemaking. Note 

that all comments received will be 

posted without change to http:// 

www.regulations.gov, including any 

personal information provided. Please 

see the discussion of the Privacy Act 

below. For detailed instructions on 

submitting comments and additional 

information on the rulemaking process, 

see the Public Participation heading of 

the Supplementary Information section 

of this document. 

Privacy Act: Anyone is able to search 

the electronic form of all comments 

received into any of our dockets by the 

name of the individual submitting the 

comment (or signing the comment, if 

submitted on behalf of an association, 

business, labor union, etc.). You may 

review DOT’s complete Privacy Act 

Statement in the Federal Register 

published on April 11, 2000 (65 FR 

19477–78) or you may visit http:// 

DocketInfo.dot.gov. 

Docket: For access to the docket to 

read background documents or 

comments received, go to http:// 

www.regulations.gov, or the street 

address listed above. Follow the online 

instructions for accessing the dockets. 

FOR FURTHER INFORMATION CONTACT: 

For technical issues: Mr. George 

Soodoo, Division Chief, Vehicle 

Dynamics (NVS–122), Office of Crash 

Avoidance Standards (E-mail: 

george.soodoo@dot.gov) (Telephone: 

(202) 366–2720) (Fax: (202) 366–5930) 

or Mr. Ezana Wondimneh, Division 

Chief, International Policy and 

Harmonization (NVS–133), Office of 

International Policy, Fuel Economy and 

Consumer Programs (E-mail: 

ezana.wondimneh@dot.gov) 

(Telephone: (202) 366–0846) (Fax: (202) 

493–2290). 

For legal issues: Ms. Sarah Alves, 

Office of the Chief Counsel (NCC–112) 

(E-mail: sarah.alves@dot.gov) 

(Telephone: (202) 366–2992) (Fax: (202) 

366–3820). 

You may send mail to these officials 

at National Highway Traffic Safety 

Administration, 1200 New Jersey 

Avenue, SE., Washington, DC 20590. 

SUPPLEMENTARY INFORMATION: 

Table of Contents 

I. Executive Summary 

II. Background 

III. Current Requirements of FMVSS No. 122 

IV. Harmonization Efforts 

V. Proposed Improvements to FMVSS No. 

122 

A. General 

1. New Terminology 

a. Motorcycle Categories 

b. Measurement of Deceleration and 

Stopping Distance 

2. Motorcycle Test Speed and Corrected 

Stopping Distance 

3. Test Method To Measure Peak Braking 

Coefficient 

4. Test Sequence 

5. Brake Application Force Measurement 

6. Brake Temperature Measurement 

7. Burnishing Procedure 

8. Notice of Wear 

B. Specific Performance Tests 

1. Dry Stop Test—Single Brake Control 

Actuated 

2. Dry Stop Test—All Service Brake 

Controls Actuated 

3. High-Speed Test 

4. Wet Brake Test 

5. Heat Fade Test 

6. Parking Brake System Test 

7. Antilock Brake System (ABS) 

Performance Test 

a. ABS Performance Test—Stopping 

Performance Requirement 

b. ABS Performance Test—Low-Friction to 

High-Friction Surface Transition Stop 

8. Partial Failure Test—Split Service Brake 

System 

9. Power-Assisted Braking System Failure 

Test 

C. Summary of Improvements 

VI. Costs, Benefits, and the Proposed 

Compliance Date 

VII. Differences Between the GTR and the 

NPRM 

VIII. Regulatory Analyses and Notices 

IX. Public Participation 

I. Executive Summary 

Currently, motorcycle brake systems 

must comply with a series of 

performance requirements established 

in Federal Motor Vehicle Safety 

Standard (FMVSS) No. 122, Motorcycle 

Brake Systems, in the early 1970s. 

While the motorcycle brake 

performance requirements have ensured 

a minimum level of braking 

performance, they have not kept pace 

with the advancement of modern 

technologies. The National Highway 

Traffic Safety Administration (NHTSA) 

seeks to keep its standards up to date. 

This document proposes to update 

FMVSS No. 122 based on the 

Motorcycle Brake Systems Global 

Technical Regulation (GTR), which 

reflects the capabilities of current 

technologies. Updating the standard to 

reflect modern technologies would help 

prevent the introduction of unsafe 

motorcycle brake systems on the road. 

Moreover, benefits from harmonization 

including decreased testing costs and 

ease of market entry would accrue to 

current and new manufacturers, and 

would in turn get passed on to 

consumers. While there is not 

necessarily any quantifiable safety 

benefit for this proposal since virtually 

all motorcycles sold in the U.S. can 

currently meet the proposed 

requirements, the agency is planning on 

taking several other actions to decrease 

motorcycle fatalities.1


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Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 54021 

2007), available at http://www.nhtsa.gov/ 

motorcycles/index.cfm (hereinafter ‘‘Action Plan to 

Reduce Motorcycle Fatalities’’); National Highway 

Traffic Safety Administration (NHTSA), ‘‘2006 

Motorcycle Safety Program Plan,’’ at 26 (2006), 

available at http://www.nhtsa.gov/portal/site/nhtsa/ 

menuitem.d7975d55e8abbe089ca8e410dba046a0/ 

(hereinafter ‘‘2006 Motorcycle Safety Program 

Plan’’). 

2The 1998 UNECE Agreement Concerning the 

Establishment of Global and Technical Regulations 

for Wheeled Vehicles, Equipment and Parts Which 

Can Be Fitted And/or Be Used On Wheeled 

Vehicles (1998 Agreement) was concluded under 

the auspices of the United Nations and provides for 

the establishment of globally harmonized vehicle 

regulations. This 1998 Agreement, whose 

conclusion was spearheaded by the United States, 

entered into force in 2000 and is administered by 

the UNECE’s World Forum for the Harmonization 

of Vehicle Regulations (WP.29). See http:// 

www.unece.org/trans/main/wp29/wp29wgs/ 

wp29gen/wp29age.html. 

3While the 1998 Agreement obligates such 

Contracting Parties to initiate rulemaking within 

one year of the establishment of the GTR, it leaves 

the ultimate decision of whether to adopt the GTR 

into their domestic law to the parties themselves. 

4 ‘‘Action Plan to Reduce Motorcycle Fatalities,’’ 

supra note 1, at 8. 

The substantive performance tests and 

requirements of FMVSS No. 122 have 

not been updated since their adoption 

in 1972. Since that time, motorcycle 

brake system technology has 

significantly changed and improved 

such that FMVSS No. 122 no longer 

reflects the current performance of 

motorcycle brake system technologies. 

In order to address modern braking 

technologies, the agency sought to 

improve the requirements and test 

procedures of FMVSS No. 122. These 

efforts coincided with the 2002 

adoption of the initial Program of Work 

under the 1998 United Nations’ 

Economic Commission for Europe 

(UNECE) Agreement Concerning the 

Establishment of Global and Technical 

Regulations for Wheeled Vehicles, 

Equipment and Parts Which Can Be 

Fitted And/or Be Used On Wheeled 

Vehicles (1998 Agreement).2 That 

program included motorcycle brake 

systems as one of the promising areas 

for the establishment of a GTR. The 

agency sought to work collaboratively 

on modernizing motorcycle brake 

regulations with other Contracting 

Parties to the 1998 Agreement 

(Contracting Parties), particularly 

Canada, the European Union and Japan. 

Through the exchange of information on 

ongoing research and testing and 

through the leveraging of resources for 

testing and evaluations, the agency 

participated in successful efforts that 

culminated in the establishment of the 

Motorcycle Brake Systems GTR under 

the 1998 Agreement. We believe that the 

provisions of the GTR would improve 

the current requirements and test 

procedures of FMVSS No. 122 by 

updating them to more closely reflect 

the capabilities of modern technologies. 

The U.S., as a Contracting Party of the 

1998 Agreement that voted in favor of 

establishing this GTR at the November 

15, 2006 Session of the Executive 

Committee of the 1998 Agreement, is 

obligated under the Agreement to 

initiate the process for adopting the 

provisions of the GTR.3 This proposal is 

based on the Motorcycle Brake Systems 

GTR. If NHTSA decides to adopt 

amendments to FMVSS No. 122 that 

differ from the requirements of the GTR, 

the agency will first seek to amend the 

GTR by submitting a formal proposal to 

the Executive Committee of the 1998 

Agreement, in accordance with the 

Agreement. 

This proposal, if made final, would 

improve the current FMVSS No. 122 

requirements in several areas. First, it 

would make the dry brake test 

requirement more stringent by 

specifying testing of each service brake 

control individually, with the 

motorcycle in the fully loaded 

condition. Second, the proposal would 

establish a more stringent high speed 

test requirement by specifying a slightly 

higher rate of deceleration. Third, the 

proposal would replace the existing wet 

brake test with one that better simulates 

actual in-service conditions, by spraying 

water onto the brake disc, instead of 

submerging the brake system before 

testing. Fourth, the proposal would 

specify an improved heat fade test 

procedure based on European and 

Japanese national regulations, which 

share the same test procedure and 

performance requirements. Fifth, the 

proposal would specify performance 

requirements for antilock brake systems, 

if present. Finally, the proposal would 

establish a new test requirement to 

evaluate the motorcycle’s performance 

in the event of a failure in the powerassisted braking system, if so equipped. 

Besides updating requirements and 

test procedures to help ensure the safety 

of motorcycle brake systems, the 

proposal also provides benefits from 

harmonization. Motorcycle 

manufacturers, and ultimately, 

consumers, both here and abroad, can 

expect to achieve cost savings through 

the formal harmonization of differing 

sets of standards when the Contracting 

Parties implement the new GTR. 

Motorcycles are vehicles that are 

prepared for the world market. It would 

be more economically efficient to have 

manufacturers using the same test 

procedures and meeting the same 

performance requirements worldwide. 

This proposal would help achieve these 

benefits and thus reduce the amount of 

resources utilized to test motorcycles. 

Moreover, this GTR sets the stage for 

further cooperative efforts with other 

countries facing similar problems at the 

same or even greater exposure rates, 

learning from their experience, and 

leveraging resources to jointly research 

and implement more effective vehicle 

related interventions.4

Although this proposal would add 

and update FMVSS No. 122 

performance requirements and provide 

benefits from harmonization, we 

anticipate that virtually all motorcycles 

sold in the U.S. can meet the 

requirements as proposed. The proposal 

includes several tests that would 

enhance the safe operation of a 

motorcycle: tests both at gross vehicle 

weight rating (GVWR) and lightly 

loaded vehicle weight, which ensure 

adequate braking performance at the 

two extremes of the loading conditions; 

a wet brake test that is more 

representative of the manner in which 

brakes are wetted during real world 

riding in wet conditions; a variety of 

ABS performance tests to ensure that 

motorcycles equipped with ABS have 

adequate antilock performance during 

emergency braking or on slippery road 

conditions; and a new requirement that 

addresses failure in the power-assisted 

braking system. 

Given the sources and magnitude of 

the overall safety problem posed by 

increased motorcycle fatalities, the 

agency intends to address the problem 

of motorcycle safety comprehensively, 

focusing on regulatory as well as 

behavioral countermeasure strategies. In 

October 2007, the Secretary of 

Transportation announced the Action 

Plan to Reduce Motorcycle Fatalities 

which will help reduce motorcycle 

fatalities with new national safety and 

training standards, curb the use of 

counterfeit helmet labelling, place a 

new focus on motorcycle-specific road 

improvements, provide training for law 

enforcement officers on how to spot 

unsafe motorcyclists, and create a broad 

public awareness campaign on rider 

safety. Id. at 1. 

II. Background 

FMVSS No. 122, Motorcycle brake 

systems, (49 CFR 571.122) took effect on 

January 1, 1974 (37 FR 1973, June 16, 

1972). FMVSS No. 122 specifies 

performance requirements for 

motorcycle brake systems. The purpose 

of the standard is to provide safe 

motorcycle brake performance under 

normal and emergency conditions. The 

safety afforded by a motorcycle’s 

braking system is determined by several 

factors, including stopping distance, 


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54022 Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 

5See Brake Systems on Motorcycles Proposed 

Motor Vehicle Safety Standard, 36 FR 5516 (Mar. 

24, 1971). 

6The baseline check is used to establish a specific 

motorcycle’s pre-test performance to provide a basis 

for comparison with post-test performance. This 

comparison is intended to ensure adequate brake 

performance, at reasonable lever and pedal forces, 

after numerous high-speed or wet brake stops. 

7The Working Party for Brakes and Running Gear 

(GRRF) is made up of delegates from many 

countries around the world, and who have voting 

privileges. Representatives from manufacturing and 

consumer groups also attend and participate in the 

GRRF and informal working groups that are 

linear stability while stopping, fade 

resistance, and fade recovery. A safe 

system should have features that both 

guard against malfunction and stop the 

motorcycle if a malfunction should 

occur in the normal service system. 

FMVSS No. 122 was originally 

conceived to cover each of these aspects 

of brake safety by specifying equipment 

and performance requirements 

appropriate for both two-wheeled and 

three-wheeled motorcycles. Because 

motorcycles differ significantly in 

configuration from other motor vehicles, 

the agency established a separate brake 

standard applicable only to this vehicle 

category. Many of the FMVSS No. 122 

test procedures are, however, similar to 

those for passenger cars.5

Only a few changes have been made 

to the regulation since it was 

established. In response to petitions, a 

1974 final rule changed the application 

of FMVSS No. 122 requirements for 

low-speed motor-driven cycles 

(motorcycles with 5-brake horsepower 

or less whose speed attainable in one 

mile is 30 miles per hour or less) (39 FR 

32914, Sept. 12, 1974). In 1978, NHTSA 

amended the FMVSS No. 122 parking 

brake test to clarify the test conditions 

and incorporate an interpretation 

applicable to three-wheeled motorcycles 

(43 FR 46547, Oct. 10, 1978). In 2001, 

the minimum hand lever force 

requirements for the heat fade test and 

water recovery test were decreased to 

facilitate the manufacture of 

motorcycles with combined braking 

systems (66 FR 42613, Aug. 14, 2001). 

Except for the above changes, FMVSS 

No. 122 has not been amended to keep 

pace with the advancement of modern 

brake technologies. 

III. Current Requirements of FMVSS 

No. 122 

FMVSS No. 122 applies to both twowheeled and three-wheeled 

motorcycles. Among other 

requirements, the motorcycle 

manufacturer must ensure that each 

motorcycle can meet performance 

requirements under conditions specified 

in paragraph S6, Test conditions, and as 

specified in paragraph S7, Test 

procedures. The tests in S7 include preand post-burnishment effectiveness 

tests, a fade and recovery test, a partial 

failure test, a water recovery test, and 

parking brake test. At the end of the test 

procedure sequence, the brake system 

must pass a durability inspection. All 

stops must be made without lockup of 

any wheel. 

Equipment. Each motorcycle is 

required to have either a split service 

brake system or two independently 

actuated brake systems. The former 

system encompasses a service brake 

system combined with a hand operated 

parking brake system for three-wheeled 

motorcycles. If a motorcycle has a 

hydraulic service brake system, it must 

also have a reservoir for each master 

cylinder, and a master cylinder reservoir 

label advising the proper grade of brake 

fluid. If the service brake system is a 

split hydraulic type, a failure indicator 

lamp is required. Additionally, threewheeled motorcycles must be equipped 

with a friction type parking brake with 

a solely mechanical means to retain 

engagement. The service brake system 

must be installed so that the lining 

thickness of the drum brake shoes may 

be visually inspected, either directly or 

by using a mirror without removing the 

drums, and so that disc brake friction 

lining thickness may be visually 

inspected without removing the pads. 

Pre- and post-burnish tests. The 

service brake system and each 

independently actuated service brake 

system on each motorcycle must be 

capable of stopping within specified 

distances from 30 miles per hour (mph) 

and 60 mph. The brakes are then 

burnished by making 200 stops from 30 

mph at 12 feet per second per second 

(fps2). The service brake system must 

then be capable of stopping at specified 

distances from 80 mph and from a speed 

divisible by 5 mph that is 4 mph to 8 

mph less than the maximum motorcycle 

speed. The post-burnish tests are 

conducted in the same way as the preburnish stops, and the service brakes 

must be capable of stopping the 

motorcycle within the post-burnish 

specified stopping distances. 

Fade and recovery test. The fade and 

recovery test compares the braking 

performance of the motorcycle before 

and after ten 60-mph stops at a 

deceleration of not less than 15 fps2. As 

a check test, three baseline stops 6 are 

conducted from 30 mph at 10 to 11 fps2, 

with the maximum brake lever and 

maximum pedal forces recorded during 

each stop, and averaged over the three 

baseline stops. Ten 60-mph stops are 

then conducted at a deceleration rate of 

not less than 15 fps2, followed 

immediately by five fade recovery stops 

from 30 mph at a deceleration rate of 10 

to 11 fps2. The maximum brake pedal 

and lever forces measured during the 

fifth recovery stop must be within plus 

20 pounds and minus 10 pounds of the 

baseline average maximum brake pedal 

and lever forces. 

Partial failure test. In the event of a 

pressure component leakage failure, the 

remaining portion of the service brake 

system must continue to operate and 

shall be capable of stopping the 

motorcycle from 30 mph and 60 mph 

within specified stopping distances. The 

brake failure indicator light must 

activate when the master cylinder fluid 

level decreases below the minimum 

specified level. 

Water recovery test. The water 

recovery test compares the braking 

performance of the motorcycle before 

and after the motorcycle brakes are 

immersed in water for two minutes. 

Three baseline stops are conducted from 

30 mph at 10 to 11 fps2, with the 

maximum brake lever and pedal forces 

recorded during each stop, and averaged 

over the three baseline stops. The 

motorcycle brakes are then immersed in 

water for two minutes, followed 

immediately by five water recovery 

stops from 30 mph at a deceleration rate 

of 10 to 11 fps2. The maximum brake 

pedal and lever forces measured during 

the fifth recovery stop must be within 

plus 20 pounds and minus 10 pounds 

of the baseline average maximum brake 

pedal force and the lever force. 

Parking brake test. For motorcycles 

required to be equipped with a parking 

brake system, such system must be able 

to hold the motorcycle on a 30 percent 

grade, in both forward and reverse 

directions, for 5 minutes. A parking 

brake indicator lamp must be provided. 

IV. Harmonization Efforts 

Globally, there are several existing 

regulations, directives, and standards 

that pertain to motorcycle brake 

systems. As all share similarities, the 

Contracting Parties to the 1998 

Agreement under WP.29 tentatively 

determined that the development of a 

GTR under the 1998 Agreement would 

be beneficial. During the 126th session 

of WP.29 of March 2002, the Executive 

Committee of the 1998 Agreement 

adopted a Program of Work, which 

included the development of a GTR on 

motorcycle brake systems. 

Subsequently, Canada offered to 

sponsor the GTR on motorcycle braking 

requirements at the 52nd session of the 

Working Party for Brakes and Running 

Gear (GRRF), in September 2002.7 To 


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Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 54023 

developing GTRs. Those that chose not to 

participate are kept apprised of the GTR progress 

from progress reports which are presented at the 

GRRF meetings and then posted on the UN’s Web 

site. 

8The first formal proposal for a GTR concerning 

motorcycle brake systems was presented during the 

58th GRRF session in September 2005. A more 

detailed report on the technical details, 

deliberations and conclusions, which led to the 

proposed GTR, was provided separately as informal 

document No. GRRF–58–16. Both documents will 

be available in the docket. 

9See http://www.unece.org/trans/main/wp29/ 

wp29wgs/wp29grrf/grrf-infmotobrake7.html for a 

record of all GRRF meetings and documents 

presented therein. 

10World Forum for Harmonization of Vehicle 

Regulations (WP.29), Special Resolution No. 1 

Concerning the Common Definitions of Vehicle 

Categories, Masses and Dimensions (S.R.1), U.N. 

Doc. TRANS/WP.29/1045 (Sept. 15, 2005), available 

at http://www.unece.org/trans/doc/2005/wp29/ 

TRANS-WP29-1045e.pdf. 

proceed with the development of the 

GTR, the Executive Committee endorsed 

Canada’s request to establish and chair 

an informal group on motorcycle brakes, 

at the 130th session of WP.29 in June 

2003. 

In an effort to select the best of 

existing performance requirements for a 

GTR, the U.S. and Canada conducted 

analyses of the relative stringency of 

three national motorcycle brake system 

regulations. These were the UNECE 

Regulation No. 78, FMVSS No. 122, and 

the Japanese Safety Standard JSS 12–61. 

The subsequent reports, along with 

proposed provisions of a GTR, were 

presented at GRRF meetings, and will be 

available in the docket. While using 

different methodologies, the results 

from the U.S./Canada report were 

similar to an industry-led report that 

examined the issue under the GRRF. 

These studies completed by the U.S., 

Canada, and the industry provided the 

basis for the development of the 

technical requirements of the GTR. 

The following regulations, directives 

and international voluntary standards 

were considered and used as the basis 

for the development of the GTR: 

• UNECE Regulation No. 78— 

Uniform provisions concerning the 

approval of vehicles of category L with 

regard to braking. 

• FMVSS No.122, Motorcycle brake 

systems. 

• Canada Motor Vehicle Safety 

Regulation No. 122—Motorcycle brake 

systems. (CMVSS No. 122). 

Note: FMVSS and CMVSS No. 122 are 

substantially similar. 

• Japan Safety Standard JSS12–61. 

• Australian Design Rule 33/00— 

Brake systems for motorcycles and 

mopeds. 

• International Organization for 

Standardization (ISO) 8710:1995, 

Motorcycles—Brakes and braking 

devices—tests and measurement 

methods. 

• ISO 12364:2001, Two-wheeled 

motorcycles—Antilock braking systems 

(ABS)—tests and measurement 

methods. 

• ISO 12366:2001, Two-wheeled 

mopeds—Antilock braking systems 

(ABS)—tests and measurement 

methods. 

The informal group used the feedback 

from the GRRF presentations to assist 

with the completion of the proposed 

GTR, a copy of which is being placed in 

the docket.8 Where national regulations 

or standards address the same subject, 

e.g., dry stop or heat fade performance 

requirements, the informal group 

reviewed comparative data on the 

relative stringency of the requirements 

from the research and studies and 

included the most stringent options. 

Additional testing was conducted to 

confirm or refine the testing and 

performance requirements. Qualitative 

issues, such as which wet brake test to 

include, were discussed on the basis of 

the original rationales and the 

appropriateness of the tests to modern 

conditions and technologies. In each of 

these steps, specific technical issues 

were raised, discussed, and resolved, as 

discussed below. The informal working 

group held a total of eight meetings 

concerning the development of the GTR. 

In November 2006, WP.29 approved the 

GTR on Motorcycle Brake Systems, and 

established it in the Global Registry as 

Global Technical Regulation No. 3. 

The GTR on motorcycle brake systems 

consists of a compilation of the most 

stringent and relevant test procedures 

and performance requirements from 

current standards and regulations. As a 

result of the comparison process, the 

selected performance requirements of 

the GTR are mainly drawn from the 

UNECE Regulation No. 78, the FMVSS 

No. 122 and the Japanese Safety 

Standard JSS 12–61 (JSS 12–61). The 

GTR is comprised of several 

fundamental tests, each with their 

respective test procedures and 

performance requirements. These tests 

and procedures are listed below along 

with the national regulation on which 

they are based: 

• Burnish procedure (FMVSS No. 

122) 

• Dry stop test with each service 

brake control actuated separately 

(UNECE Regulation No. 78/JSS 12–61) 

• Dry stop test with all service brake 

systems applied simultaneously 

(FMVSS No. 122) 

• High speed test (JSS 12–61) 

• Wet brake test (UNECE Regulation 

No. 78/JSS 12–61) 

• Heat fade test (UNECE Regulation 

No. 78/JSS 12–61) 

• Parking brake test (UNECE 

Regulation No. 78/JSS 12–61) 

• ABS tests (UNECE Regulation No. 

78/JSS 12–61) 

• Partial failure test—split service 

brake systems (FMVSS No. 122) 

• Power-assisted braking system 

failure test (new) 

The GTR process was transparent to 

country delegates, industry 

representatives, public interest groups, 

and other interested parties. Information 

regarding the meetings and negotiations 

was publicly available through notices 

published periodically by the agency 

and UN Web site.9 In the U.S., NHTSA 

published notice of its intent to add 

motorcycle brake systems to its list of 

recommendations of standards for 

consideration as a GTR in January 2001 

(66 FR 4893, Jan. 18, 2001; Docket No. 

NHTSA–00–7538). The agency later 

published notice that Canada had 

submitted a proposal for the 

establishment of a motorcycle brakes 

GTR, and sought public comment on the 

formal proposal (69 FR 60460, Oct. 8, 

2004; Docket No. NHTSA–03–14395). In 

October 2006, NHTSA published a 

further update on the status of the 

proposed motorcycle brake systems 

GTR, and requested comments specific 

to the motorcycle brakes GTR and 

NHTSA’s intent to vote positively on 

behalf of the United States for its 

establishment (71 FR 59582, Oct. 10, 

2006; Docket No. NHTSA–2003–14395). 

The agency did not receive comments in 

response to any of these notices 

regarding the motorcycle brake systems 

GTR. 

V. Proposed Improvements to FMVSS 

No. 122 

A. General 

1. New Terminology 

For this proposal, definitions in 

FMVSS No. 122 (paragraph S4) were 

revised or added where necessary, such 

as new proposed terms used to describe 

antilock brake systems (ABS), vehicle 

maximum speed (Vmax), and peak 

braking coefficient (PBC). Additionally, 

in order to streamline the proposed 

regulatory text to more closely reflect 

the GTR text, some of the new proposed 

terms are common terminology and 

definitions based on the UN document 

titled ‘‘Special Resolution No. 1 

Concerning the Common Definitions of 

Vehicle Categories, Masses and 

Dimensions (S.R.1)’’ 10 (UN Doc. S.R.1) 

developed for the purposes of the GTRs. 

Thus, certain new definitions that may 


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54024 Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 

11 49 CFR 571.122, S6.1. ‘‘Unloaded vehicle 

weight’’ is defined under 49 CFR 571.3(b) to mean 

‘‘the weight of a vehicle with maximum capacity of 

all fluids necessary for operation of the vehicle, but 

without cargo, occupants, or accessories that are 

ordinarily removed from the vehicle when they are 

not in use.’’ 12Lightly loaded means the sum of unladen 

vehicle mass (mass of the vehicle with bodywork 

and all factory fitted equipment, and fuel tanks 

filled to at least 90 percent) and driver mass ‘‘plus 

15 kg for test equipment, or the laden condition, 

whichever is less.’’ FMVSS No. 122 S4, Definitions 

(proposed). 

13See WP.29, Amendment to Special Resolution 

No. 1 Concerning the Common Definitions of 

Vehicle Categories, Masses, and Dimensions, U.N. 

Doc. ECE/TRANS/WP.29/1045/Amend.1 (May 9, 

2007), available at http://www.unece.org/trans/ 

main/wp29/wp29wgs/wp29gen/wp29fdoc/1000/ 

ECE-TRANS-WP29-1045a1e.pdf. 

be similar to existing 49 CFR Part 571 

definitions are proposed to be added to 

§ 571.122 S4, Definitions. For example, 

current FMVSS No. 122 specifies that 

performance requirements must be met 

when the ‘‘motorcycle weight is 

unloaded vehicle weight plus 200 

pounds.’’ 11 This is effectively 

equivalent to the mass term ‘‘lightly 

loaded’’ in the proposed rule, which is 

the testing condition specified for the 

proposed dry stop test—all service brake 

controls actuated, the high-speed test, 

the antilock brake systems tests, and the 

partial failure test.12 These proposed 

terms, some of which may be similar or 

equivalent to existing terms defined 

elsewhere in 49 CFR Part 571, are used 

in the motorcycle brakes GTR in an 

effort to streamline the GTR and 

maximize harmonization benefits. 

Additionally, the proposed rule 

divides motorcycles into five categories, 

which are referenced in the GTR. These 

motorcycle categories are based on 

number of wheels and maximum speed, 

and were originally defined in the UN 

Doc. S.R.1, as amended in May 2007.13

We included these categories in the 

definitions portion of proposed FMVSS 

No. 122 because under the GTR some 

performance tests do not apply to 

certain motorcycle categories, and 

certain motorcycle categories have 

different performance requirements than 

others. 

Category 3–1 and category 3–3 

motorcycles are two-wheeled 

motorcycles. Category 3–1 motorcycles 

are two-wheeled motorcycles with an 

engine cylinder capacity not exceeding 

50 cm3 and a maximum design speed 

not exceeding 50 kilometers per hour 

(km/h). Category 3–3 motorcycles are 

two-wheeled motorcycles with an 

engine cylinder capacity exceeding 50 

cm3 or a maximum design speed 

exceeding 50 km/h. Category 3–2 

motorcycles are three-wheeled 

motorcycles of any wheel arrangement 

with an engine cylinder capacity not 

exceeding 50 cm3 and a maximum 

design speed not exceeding 50 km/h. 

Category 3–4 motorcycles are those 

manufactured with three wheels 

asymmetrically arranged in relation to 

the longitudinal median plane with an 

engine cylinder capacity exceeding 50 

cm3 or a maximum design speed 

exceeding 50 km/h. Finally, category 3– 

5 motorcycles are motorcycles 

manufactured with three wheels 

symmetrically arranged in relation to 

the longitudinal median plane with an 

engine cylinder capacity exceeding 50 

cm3 or a maximum design speed 

exceeding 50 km/h. 

2. Vehicle Test Speed and Corrected 

Stopping Distance 

Deceleration or stopping distance 

performance requirements are set for a 

specified initial test speed. While 

professional test riders can approach 

this initial test speed, it is unlikely that 

the test will be started at the exact speed 

specified, affecting the stopping 

distance measurement. The current 

FMVSS No. 122 does not specify a 

speed tolerance for this potential 

variation, but consistent with the GTR, 

the proposed rule specifies Japan’s 

existing general tolerance of ±5 km/h in 

S6.1.4. 

A method for correcting the measured 

stopping distance is specified in JSS 12– 

61 to compensate for the difference 

between the specified test speed and the 

actual speed where the brakes were 

applied. Although not specified directly 

in the regulations, the current FMVSS 

No. 122 and CMVSS No. 122 also apply 

a correction factor to test data, using the 

method specified in Society of 

Automotive Engineers (SAE) standard 

J299, Stopping Distance Test Procedure. 

The informal group evaluated the above 

noted stopping distance correction 

methods and the one specified in ISO 

8710:1995, Motorcycles—Brakes and 

braking devices—tests and 

measurement methods. 

SAE J299 offers the most basic 

method for estimating the corrected 

distance, and the method is applicable 

to a speed tolerance of ± 3.2 km/h (± 2 

mph). The ISO 8710 and JSS 12–61 

methods are based on the same 

principles, but also take into 

consideration the brake system reaction 

time. These methods are applicable to a 

wider speed tolerance of ± 5 km/h. 

However, a small error in handling the 

system reaction time is apparent in the 

ISO 8710 equation, which results in 

higher than expected corrected values. 

Based on this analysis, the informal 

group agreed that the stopping distance 

correction method specified in JSS 12– 

61 was the most appropriate for the 

GTR. Therefore, as with the existing 

Japanese standard, the specified test 

speeds in the GTR include a general 

tolerance of ± 5 km/h (S6.1.4), using the 

JSS stopping distance correction method 

to normalize the measured test results, 

if necessary, to compensate for the 

difference between the specified test 

speed and the actual speed where the 

brakes were applied (see S5.3.2(b)). 

3. Test Method To Measure Peak 

Braking Coefficient 

The peak braking coefficient (PBC) is 

a measure of the coefficient of friction 

of the test surface and is an important 

parameter in evaluating the brake 

performance of a vehicle. PBC is 

effectively equivalent to the peak 

friction coefficient (PFC) as defined in 

FMVSS No. 121, Air brake systems, and 

FMVSS No. 135, Light vehicle brake 

systems. The GTR specifies test surface 

conditions, one of which is that the 

high-friction ‘‘test surface has a nominal 

[PBC] of 0.9, unless otherwise 

specified.’’ For reasons of objectivity, 

we are specifying in the proposed rule 

a PBC equal to 0.9 for the high-friction 

dry test surface used for the motorcycle 

brake system tests. NHTSA has 

discussed the issues surrounding 

objective measurement of PBC/PFC at 

length in an early-1990s rulemaking that 

added ABS requirements for medium 

and heavy vehicles (see e.g., 60 FR 

13216, Mar. 10, 1995; Docket Nos. 92– 

29, 93–69). 

FMVSS No. 122 currently specifies 

that the road tests be conducted on an 

8-foot-wide level roadway having a skid 

number of 81. The skid number is also 

a measure of the coefficient of friction 

of the test surface and is derived by 

measuring the friction using a locked 

wheel, whereas the PBC is derived by 

measuring the peak surface friction 

before wheel lockup occurs. PBC is a 

more relevant surface friction 

measurement for non-locked wheel 

tests, as those included in FMVSS No. 

122 and in the GTR. Other Federal 

motor vehicle safety standards for 

braking systems, FMVSS No. 121 and 

FMVSS No. 135, specify the road test 

surface using PBC of 0.9 when measured 

using the American Society for Testing 

and Materials (ASTM) E1136–93 

(Reapproved 2003) standard reference 

test tire, in accordance with ASTM 

Method E1337–90 (Reapproved 2002), at 

a speed of 40 mph without water 

delivery. 

The UNECE Regulation No. 78 and 

the JSS 12–61 do not specify the 

coefficient of friction for the test surface 

but prescribe that the test surface be 

level, dry, and affording good adhesion. 

For the ABS tests where road surface 


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friction requirements are specified, the 

UNECE Regulation No. 78 and JSS 12– 

61 specify a method that is based on the 

same principles as measuring the PBC. 

This is determined by finding the wheel 

lock threshold through a series of 

braking tests with the ABS disabled for 

the individual motorcycle being 

evaluated, and uses the tires on the 

motorcycle compared with the ASTM 

Method, which uses a reference test 

(control) tire on a skid trailer. 

The GTR defines the test surface using 

a PBC value instead of a skid number 

value since peak braking coefficient is a 

more representative measure of the type 

of braking tests performed in the 

requirements with a rolling tire. 

However, the decision was made to not 

specify the method used to measure the 

coefficient of friction but leave it to the 

national regulations to specify which of 

the above test methods should be used 

to measure PBC. In the U.S., the ASTM 

Method for measuring PBC to define 

surface friction has been included in 

Federal motor vehicle safety standards 

since the early-1990’s and was also used 

by the U.S. automotive industry prior to 

that date. Accordingly, the agency 

proposes that the PBC of the test surface 

will be measured using the ASTM 

E1136–93 (Reapproved 2003) standard 

reference test tire, in accordance with 

ASTM Method E1337–90 (Reapproved 

2002). 

As mentioned above, the GTR also 

maintains an option for Contracting 

Parties to specify in their respective 

national regulations the value of PBC for 

the high-friction dry test surface used 

for the motorcycle brake system tests. 

Because of objectivity concerns, we are 

proposing a PBC of 0.9 as opposed to a 

nominal PBC of 0.9 (the default option 

in the GTR). 

4. Test Sequence 

We are proposing a specific testing 

order to eliminate any potential effect of 

the test sequence on braking 

performance and to harmonize with the 

GTR. The proposed sequence was 

selected based on increasing severity of 

the test on the motorcycle and its brake 

components, in order to preserve the 

condition of the brakes. 

The current FMVSS No. 122 specifies 

a particular sequence in which tests 

should be conducted, ending with the 

wet brake test. The purpose here is to 

minimize the variability of test results 

through consistency in both the 

condition of the brakes throughout the 

tests and in the way in which the brakes 

are evaluated. There is no specified test 

order in the UNECE Regulation No. 78. 

Similarly, JSS 12–61 indicates that tests 

can be done in any order, with the 

exception that the fade test be 

conducted last. 

The fade test would have the greatest 

effect on the condition of the motorcycle 

brakes, which could affect brake 

performance in subsequent tests. For 

this reason, current FMVSS No. 122 

specifies that a re-burnishing be 

conducted after the fade test, to refresh 

the brake components. In order to 

eliminate the need for re-burnishing, the 

GTR specifies that the fade test be the 

last of the motorcycle brake system 

performance tests, which is consistent 

with the existing practice in JSS 12–61. 

The ABS test would be the next most 

severe test, which will result in braking 

at or near the limits of traction. Thus, 

the GTR specifies that the ABS test 

would precede the fade test, for 

motorcycles equipped with ABS. The 

remaining tests are not as severe on the 

brake system and tires, therefore the 

GTR sequenced them according to 

increasing test speed for the dry stop 

performance tests, followed by the wet 

brake performance test. 

Consistent with the GTR, we are 

proposing a specified test sequence as 

follows: 

(1) Dry stop test—single brake control 

actuated; 

(2) Dry stop test—all service brake 

controls actuated; 

(3) High speed test; 

(4) Wet brake test; 

(5) If fitted: 

(a) Parking brake system test; 

(b) ABS test; 

(c) Partial failure, for split service 

brake systems test; 

(d) Power-assisted braking system 

failure test. 

(6) Heat fade test. 

The informal group that developed 

the technical specifications for the GTR 

assessed alternatives to the testing 

sequence, including selecting a test 

sequence based on the loading of the 

motorcycle in order to save time, and 

relocating the wet brake test to secondlast, before the final fade test. Either 

option would place the more severe 

brake tests earlier in the test sequence, 

which could affect braking performance 

in subsequent tests. The GTR therefore 

kept the test sequence as noted above. 

5. Brake Application Force 

Measurement 

Controls for the application of the 

brakes can include hand and foot 

actuated control levers. The various 

national standards and regulations have 

slightly different brake control input 

force limits, and in the case of a hand 

actuated control lever, there is also a 

discrepancy as to the location of 

application of the input force. One 

consistent element is the location and 

direction of application of the input 

force to the foot actuated lever (i.e. 

pedal). Consistent with the GTR, the 

proposed rule specifies input forces in 

accordance with the national regulation 

on which the individual test is based, to 

minimize confusion. 

The respective input forces are noted 

in the following table: 

Regulation Foot control, FP (N) Hand control, FL (N) 

FMVSS No. 122 ........................................................................................................................... 25 < FP < 400 ............. 10 < FL < 245 

UNECE Regulation No. 78/JSS 12–61 ........................................................................................ FP < 350 ...................... FL < 200 

A discussion on brake control actuation 

force specifications for evaluating 

motorcycles equipped with ABS is 

provided below in paragraph V.B.7. 

With respect to the location of the 

input force on the hand-controlled 

lever, UNECE Regulation No. 78 and JSS 

12–61 place the input force 50 mm from 

the end of the lever, while FMVSS No. 

122 locates the input force 30 mm from 

the end of the handle bar grip. On most 

models (but not all), the control lever 

typically extends slightly beyond the 

handle bar grip, such that the control 

forces are almost at the same location 

regardless of the method followed. 

Depending on the regulation, however, 

it is not entirely clear whether this 

measurement should be taken along the 

length of the control lever or parallel to 

the handle bar grip; or, how to measure 

with a curved or angled control lever. 

Some interpretation is required. 

In developing the GTR, there was 

agreement that none of the three 

national regulations is clear enough 

with respect to measuring the location 

of the input force on the handcontrolled lever. In an effort to define a 

common practice, the GTR includes a 


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54026 Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 

revised description for the location of 

the input force on the control lever and 

its direction of application, based on 

ISO 8710:1995, Motorcycles—Brakes 

and braking devices—tests and 

measurement methods. This proposed 

rule adopts the GTR’s harmonized 

specification of input force. 

Finally, for those motorcycles that use 

hydraulic fluid for brake force 

transmission, the GTR stipulates that 

the master cylinder shall have a sealed, 

covered, separate reservoir for each 

brake system. This includes one or more 

separate reservoirs located within the 

same container, such as commonly 

found on passenger cars. Such 

containers may only have one sealed, 

covered filling cap. The proposed rule 

incorporates these hydraulic service 

brake system requirements in S5.1.9. 

6. Brake Temperature Measurement 

Brake test requirements typically 

specify that initial brake temperature 

(IBT) be measured at the start of each 

braking performance run to enhance test 

repeatability. The two measurement 

methods that are generally used in brake 

standards and regulations worldwide 

include (1) the use of plug-type 

thermocouples, and (2) the use of 

rubbing-type thermocouples. We 

propose to retain the plug-type 

thermocouples brake temperature 

measurement method in FMVSS No. 

122. 

Plug-type thermocouples are 

imbedded in the brake friction material 

(brake pad for disc brakes or brake shoes 

for drum brakes) one millimeter below 

the contact surface between the friction 

material and the brake disc or brake 

drum. This placement of the 

thermocouple allows no contact with 

the friction surfaces and provides an 

accurate reading of the temperature at 

the friction material/disc or drum 

interface. Rubbing-type thermocouples 

are placed so that they are in direct 

contact with both the friction material 

and the disc or drum. Although this 

type of thermocouple can provide a 

quicker response to temperature 

changes, it has some limitations 

regarding its durability and its 

effectiveness when used on brakes with 

cross-drilled or grooved discs. In 

addition, for a given brake system, the 

rubbing-type thermocouple generally 

provides higher temperature readings 

compared with the plug-type 

thermocouple. 

The two methods of measuring the 

IBT were included in the GTR and each 

Contracting Party may specify which 

temperature measurement would be 

accepted in its national regulation. 

FMVSS No. 122, as well as all the other 

brake standards in the Federal motor 

vehicle safety standards, currently 

specifies the plug-type thermocouple for 

measuring the initial brake temperature. 

UNECE Regulation No. 78 and JSS 12– 

61 also prescribe brake temperature 

measurement, but neither regulation 

makes reference to specific 

measurement equipment or installation 

methods. NHTSA does not have 

experience using the rubbing-type 

thermocouple either in brake research or 

compliance testing. Given the 

limitations of the rubbing-type 

thermocouple, we believe that the plugtype thermocouple would be the more 

effective option for measuring IBT in the 

proposed FMVSS No. 122. Therefore, 

the proposed rule specifies that initial 

brake temperature is measured by plugtype thermocouples. 

With respect to the actual brake 

temperature values specified for testing 

purposes, each of the national 

regulations on which the GTR 

performance requirements are based 

specifies a value for the IBT. For most 

tests, the UNECE Regulation No. 78 and 

JSS 12–61 specify that the IBT shall be 

less than or equal to 100 °C (212 °F), 

whereas FMVSS No. 122 specifies an 

IBT between 55 °C and 65 °C (130 °F 

and 150 °F). In developing the GTR, it 

was agreed that a narrow IBT range 

could improve the repeatability of the 

performance tests. However, test data 

indicated that the narrow range 

specified by FMVSS No. 122 might not 

be achievable for those motorcycles 

equipped with a combined brake 

system. Therefore, the GTR specifies an 

IBT between 55 °C and 100 °C in order 

to encompass all brake systems, and the 

proposed rule specifies this same IBT 

range as a test condition. 

7. Burnishing Procedure 

The current FMVSS No. 122 includes 

a burnishing procedure. In order to 

harmonize with the GTR, we are 

proposing a slight variation of the 

current procedure, to include some 

aspects of procedures currently used by 

motorcycle manufacturers in 

preparation for UNECE Regulation No. 

78/JSS 12–61 type approval testing. 

The burnishing procedure serves as a 

conditioning of the foundation brake 

components to permit the brake system 

to achieve its full capability. Burnishing 

typically matches the friction 

components to one-another and results 

in more stable and repeatable stops 

during testing. UNECE Regulation No. 

78 and JSS 12–61 do not include any 

burnishing procedure. Under the 

UNECE and the JSS regulations, the 

motorcycle is generally presented for 

type approval compliance testing in a 

burnished condition, using a procedure 

determined by the motorcycle 

manufacturer. All Federal motor vehicle 

safety standards for brake systems 

(FMVSS Nos. 105, 121, 122 and 135) 

currently include a burnishing 

procedure. The burnishing procedure of 

FMVSS No. 122 specifies 200 stops with 

both brakes applied simultaneously, 

decelerating from a speed of 30 mph at 

12 fps2 with an IBT between 55 °C and 

65 °C (130 °F and 150 °F). 

The burnishing procedure in the GTR 

is based on FMVSS No. 122, but also 

includes some aspects of procedures 

currently used by motorcycle 

manufacturers in preparation for 

UNECE Regulation No. 78/JSS 12–61 

type approval testing. For example, the 

initial speed proposed for the procedure 

has been changed to 50 km/h to roundoff the metric equivalent, which is a 

slight increase from 30 mph (48 km/h) 

as specified by FMVSS No. 122. An 

initial speed of 0.8 Vmax was adopted 

for category 3–1 and 3–2 motorcycles, 

which have a Vmax of 50 km/h or less. 

Instead of making complete stops, the 

proposal also includes braking the 

motorcycle at the specified deceleration 

down to a speed between 5 km/h and 10 

km/h, after which the motorcycle may 

be accelerated to the initial test speed 

for the next stop in the burnishing 

procedure. The primary reason for not 

braking the motorcycle to a complete 

stop is to expedite the burnishing 

procedure. The increased motorcycle 

kinetic energy resulting from the small 

initial speed increase of 2 km/h is likely 

to offset any reduction in kinetic energy 

resulting from not braking the 

motorcycle until a complete stop is 

reached. The GTR specifies burnishing 

the brakes separately since this would 

result in a more complete burnish for 

both front and rear brakes, as compared 

with the current FMVSS No. 122 

method of using both brakes 

simultaneously. Hence, consistent with 

the GTR, the proposed rule specifies 

that each brake be burnished for 100 

decelerations. 

Finally, the GTR changes the IBT from 

the range of 55 °C to 65 °C currently 

specified in FMVSS No. 122 to an IBT 

less than or equal to 100 °C. The 

primary reasons for changing the IBT 

are to accommodate the higher 

operational temperatures of motorcycles 

equipped with disc brakes and to reduce 

the cooling times between stops. In 

developing the GTR, it was agreed that 

although a narrow IBT range is 

important to achieve good repeatability 

of the performance tests, the IBT range 

is not as critical for the burnishing 

procedure. 


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14As mentioned above, current FMVSS No. 122 

specifies that performance requirements must be 

met when the ‘‘motorcycle weight is unloaded 

vehicle weight plus 200 pounds.’’ 49 CFR 571.122, 

S6.1. ‘‘Unloaded vehicle weight’’ is defined under 

49 CFR 571.3(b) to mean ‘‘the weight of a vehicle 

with maximum capacity of all fluids necessary for 

operation of the vehicle, but without cargo, 

occupants, or accessories that are ordinarily 

removed from the vehicle when they are not in 

use.’’ This current FMVSS No. 122 test mass 

condition is effectively equivalent to the mass 

condition ‘‘lightly loaded’’ in the proposed rule. 

Lightly loaded means the sum of unladen vehicle 

mass (mass of the vehicle with bodywork and all 

factory fitted equipment, and fuel tanks filled to at 

least 90 percent) and driver mass ‘‘plus 15 kg for 

test equipment, or the laden condition, whichever 

is less.’’ FMVSS No. 122 S4, Definitions (proposed). 

15These studies will be posted in the current 

docket. 

8. Notice of Wear 

We are proposing the GTR 

requirement that ‘‘friction material 

thickness shall be visible without 

disassembly, or where the friction 

material is not visible, wear shall be 

assessed by means of a device designed 

for that purpose.’’ FMVSS No. 122 

S5.2.2, Notice of wear (proposed). 

Current FMVSS No. 122 requires that 

the ‘‘brake system [ ] be installed so that 

the lining thickness of drum brake shoes 

may be visually inspected, either 

directly or by use of a mirror without 

removing the drums, and so that disc 

brake friction lining thickness may be 

visually inspected without removing the 

pads.’’ FMVSS No. 122 S5.1.5, Other 

requirements. Allowing wear of friction 

material thickness to be assessed either 

visually or by means of a device 

increases design freedom while serving 

the same purpose of indicating friction 

material wear, without the need for 

disassembly. 

B. Specific Performance Tests 

1. Dry Stop Test—Single Brake Control 

Actuated 

The GTR has a provision for a dry 

stop test with single brake control that 

is based on UNECE Regulation No. 78 

and JSS 12–61 tests. Current FMVSS No. 

122 does not have a requirement that 

tests each brake system separately in a 

split brake service system, but only a 

requirement that tests the front and rear 

brake simultaneously. In the main 

FMVSS No. 122 dry stop test with both 

brake controls actuated simultaneously, 

the test rider judges how to apportion 

the force actuated to the front and rear 

brakes. This may give less repeatable 

test results or allow the test rider to 

compensate for a ‘‘weak’’ brake. As 

such, an additional test specifying that 

each split brake be tested individually 

would improve FMVSS No. 122. 

The purpose of a dry stop test 

requirement with the separate actuation 

of each brake control is to ensure a 

minimum level of motorcycle braking 

performance on a dry road surface for 

each independent brake system. Each of 

the major national motorcycle brake 

regulations, UNECE Regulation No. 78, 

FMVSS No. 122, and JSS 12–61, 

includes a dry stop test in its test 

procedures. The UNECE Regulation No. 

78 and the JSS 12–61 test procedures 

and performance requirements are 

similar. The UNECE Regulation No. 78 

and JSS 12–61 regulations require that 

the braking performance be evaluated 

separately for each brake control, with 

the motorcycle in the laden condition 

and at test speeds of 40 km/h or 60 km/ 

h depending on the motorcycle 

category. The only exception is for 

motorcycle category 3–4, where it is 

specified that the brakes at all wheels 

shall be operated via a single foot 

actuated control. 

Current FMVSS No. 122 performance 

requirements are quite different as they 

specify motorcycles be tested in what is 

effectively the lightly-loaded 

condition,14 and with all brake controls 

actuated simultaneously. The exception 

is the pre-burnish test requirements, 

which specify that each independently 

actuated service brake system must be 

capable of stopping the motorcycle (in 

effectively the lightly-loaded condition) 

within specified stopping distances. 

Current FMVSS No. 122 also specifies 

test requirements from 30 mph (48.3 

km/h), 60 mph (96.6 km/h) and 80 mph 

(128.8 km/h). Consistent with being 

tested in the lightly-loaded condition 

and with both brakes applied together, 

the FMVSS No. 122 deceleration 

requirements are higher than in the 

UNECE Regulation No. 78 and JSS 12– 

61. The FMVSS No. 122 and the UNECE 

Regulation No. 78/JSS 12–61 tests are 

conducted with the engine 

disconnected, which means that only 

the foundation brake performance is 

measured and engine braking is not a 

factor. Although current FMVSS No. 

122 also specifies that independent 

service brake systems be evaluated 

separately, that test is conducted with 

the brakes in the pre-burnished 

condition, hence requiring a lower level 

of performance. 

In independent studies of the relative 

severity of the tests as they apply to 

category 3–3 motorcycles, the industry 

concluded that the UNECE Regulation 

No. 78/JSS 12–61 test was marginally 

more stringent, whereas the NHTSA/ 

Transport Canada findings indicated 

that the FMVSS No. 122 test was 

marginally more stringent.15 Despite the 

difference in these findings, neither 

study demonstrated a significant 

difference in stringency between these 

national regulations. 

The primary advantage of the UNECE 

Regulation No. 78/JSS 12–61 

requirement is that each brake control is 

tested separately, which ensures that 

each independent brake system meets 

specific performance criteria. As 

mentioned above, in the main FMVSS 

No. 122 dry stop test with both brake 

controls actuated simultaneously, the 

test rider judges how to apportion the 

force actuated to the front and rear 

brakes. This may give less repeatable 

test results or allow the test rider to 

compensate for a ‘‘weak’’ brake. 

Therefore, consistent with the GTR, the 

proposed rule includes the dry stop test 

with single brake control based on 

UNECE Regulation No. 78/JSS 12–61 

requirements. Unlike present UNECE/ 

JSS national standards, the performance 

requirement can be met only through 

measurement of the stopping distance. 

2. Dry Stop Test—All Service Brake 

Controls Actuated 

The GTR contains a provision to test 

the service brakes with the brake control 

applied simultaneously, which is very 

similar to the current FMVSS No. 122 

dry stop test with both brake controls 

actuated simultaneously. The purpose 

of this test with all service brake 

controls actuated is to evaluate the full 

braking performance of motorcycles 

from a speed of 100 km/h with both 

front and rear brakes applied 

simultaneously. The current FMVSS No. 

122 includes a stopping distance test 

from 60 mph (96 km/h) with all brake 

controls actuated simultaneously, with 

the motorcycle in the lightly-loaded 

condition. The stopping distance 

requirement from this speed is 185 feet 

(56.4 meters), which is equivalent to an 

average deceleration of 6.4 m/s2 over the 

entire stop. The current requirements of 

UNECE Regulation No. 78 and JSS 12– 

61 do not include a performance test 

from such a speed. 

The GTR performance specifications 

are based on the FMVSS No. 122 test 

noted above. These test parameters are 

relevant since they represent the typical 

operating conditions of a motorcycle 

with a single rider traveling at highway 

speeds. In addition, testing in the lightly 

loaded condition with a full brake 

application helps to evaluate motorcycle 

stability during braking. Consistent with 

the GTR, in the proposed rule this test 

would apply to motorcycle categories 3– 

3, 3–4 and 3–5, but not to motorcycle 

categories 3–1 and 3–2. The latter are 

motorcycles with a maximum speed of 

less than 50 km/h. Given this speed 

restriction, motorcycle categories 3–1 

and 3–2 will use a test speed based on 


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54028 Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 

16This study will be posted in the current docket. 

90 percent of the maximum speed, or 

almost at the same exact speed as the 40 

km/h test speed for the dry stop test— 

single brake control actuated. As the 

level of stringency was deemed 

comparable for both dry stop tests, it 

was agreed that specifying a dry stop 

test with all the service brake controls 

actuated for motorcycle categories 3–1 

and 3–2 would be redundant. 

The brake application force specified 

in the GTR is less than or equal to 245 

N for hand levers and less than or equal 

to 400 N for foot pedals. Since this GTR 

performance requirement is adopted 

from FMVSS No. 122, with a slight 

increase in speed to 100 km/h from 96 

km/h, the GTR retained the 

corresponding control lever/pedal force 

parameters to maintain the stringency of 

the original test. If this dry stop test was 

adopted with the force parameters from 

UNECE Regulation No. 78 and JSS 12– 

61 Standards (200 N/350 N for the hand 

lever/foot pedal controls, respectively), 

it would increase the stringency of the 

test since it would effectively be 

proposing that the current FMVSS No. 

122 performance requirements be met 

with lower application forces. 

The stopping distance performance 

requirement from a speed of 100 km/h 

is 198.5 feet (60.5 meters). In keeping 

with the original requirements on which 

this test is based (rounded to 100 km/ 

h), the GTR maintains the performance 

requirement for this dry stop test in 

terms of stopping distance only. 

The approach for setting forth the 

performance requirements in current 

FMVSS No. 122 is to specify 

progressively higher performance 

requirements at set break points as test 

speeds decrease, based mainly on the 

fact that the PBC increases as the 

motorcycle speed decreases. When 

viewed in the context of FMVSS No. 

122, the placement of break points are 

provided to accommodate the current 

FMVSS No. 122 test requirements from 

speeds of 30 mph, 60 mph, 80 mph and 

up to 120 mph. However, for the 

purpose of the GTR, it became evident 

that maintaining the original FMVSS 

No. 122 break points would have the 

unintended effect of introducing two 

levels of stringency that are dependent 

on the test speed, making it inconsistent 

with the other dry stop tests in the 

GTR—i.e., both the high speed test and 

the dry stop test single brake control 

actuated have constant performance 

requirements irrespective of the test 

speed. For this reason, the GTR contains 

a single performance requirement based 

on the 100 km/h performance 

requirement in the current FMVSS No. 

122, for all motorcycles to which this 

test applies. 

3. High-Speed Test 

The purpose of the high-speed test is 

to evaluate the full braking performance 

of the motorcycle from a high speed and 

with both front and rear brakes applied 

simultaneously. Each of the major 

national motorcycle brake regulations, 

UNECE Regulation No. 78, FMVSS No. 

122, and JSS 12–61, includes a highspeed test in its requirements. The 

UNECE Regulation No. 78 and the JSS 

12–61 tests are similar and are 

performed from a speed of 160 km/h or 

0.8 of the vehicle’s maximum speed 

(Vmax), whichever is less. The UNECE 

Regulation No. 78 test requires that 

motorcycle braking performance and 

behavior be recorded; however, it does 

not have specific performance 

requirements. The performance required 

by JSS 12–61 includes achieving a mean 

fully developed deceleration (MFDD) of 

at least 5.8 m/s2 or coming to a stop 

prior to the equivalent braking distance. 

The high-speed effectiveness test of 

FMVSS No. 122 is conducted from a test 

speed that is based on the speed 

capability of the motorcycle, not 

exceeding 193.2 km/h (120 mph). When 

tested at the maximum speed of 120 

mph, the required stopping distance is 

861 feet (262.5 meters), equivalent to an 

average deceleration of 5.5 m/s2. Based 

on these figures, the FMVSS No. 122 

test appears to be more stringent due to 

the higher test speed, whereas the JSS 

12–61 appears to be more stringent 

based on a deceleration requirement. 

The test conditions for current 

FMVSS No. 122 and the UNECE 

Regulation No. 78/JSS 12–61 high speed 

tests are quite similar, including the 

motorcycle test mass and the 

simultaneous application of both brakes. 

The main difference between test 

parameters, besides the difference in the 

motorcycle test speeds, is that the 

FMVSS No. 122 test is conducted with 

the engine disconnected (clutch 

disengaged), whereas the UNECE 

Regulation No. 78/JSS 12–61 test is 

conducted with the engine connected 

(clutch engaged). With a connected 

engine, the subsequent engine braking 

can assist in the deceleration of the 

motorcycle. This effect is reduced to a 

minimum by placing the transmission 

in the highest gear during the braking 

maneuver. The benefit of having the 

engine connected is the effect of 

stabilizing the motorcycle while braking 

from such a high speed. 

Based on the NHTSA/Transport 

Canada Review of Motorcycle Brake 

Standards,16 it was determined during 

development of the GTR that 100 mph 

(160 km/h) or 0.8 Vmax is adequate for 

a high speed effectiveness test since the 

benefits of testing from higher speeds do 

not warrant the potential hazard to 

which the rider is exposed. The GTR 

limits the test speed to 160 km/h to 

address test facility limitations and 

safety concerns. The FMVSS No. 122 

and JSS 12–61 performance 

requirements are very similar from a 

maximum speed of 160 km/h. The 

equivalent average deceleration in 

FMVSS No. 122 is 5.5 m/s2 from 100 

mph, compared to the JSS 12–61 MFDD 

of 5.8 m/s2 from 160 km/h. In actual 

testing, the performance differences for 

the high-speed tests were too small to 

clearly identify one testing procedure as 

being more stringent than the other. The 

GTR also specifies that the high speed 

test be conducted with the motorcycle 

engine connected and the transmission 

in the highest gear, per JSS 12–61, 

which has the effect of enhancing 

motorcycle stability during braking from 

test speeds of 160 km/h. 

4. Wet Brake Test 

The proposed wet brake test provision 

differs from the current FMVSS No. 122 

wet brake test in that instead of 

submerging the brake system in water 

and then testing the brakes, the water is 

sprayed directly onto the brakes during 

the test. This procedure is based on 

UNECE Regulation No. 78 and JSS 12– 

61, which the reviews of motorcycle 

brake standards found to be more 

stringent than current FMVSS No. 122. 

Accordingly, we believe that motorcycle 

brake safety will be enhanced as a result 

of this change in wet brake test 

procedure. 

The purpose of the wet brake test is 

to ensure a minimum level of braking 

performance when the motorcycle is 

ridden in heavy rain conditions. Each of 

the major national motorcycle brake 

regulations, UNECE Regulation No. 78, 

FMVSS No. 122, and JSS 12–61, 

includes a wet brake test, but different 

philosophies are found in them. The 

UNECE Regulation No. 78 and the JSS 

12–61 test procedures and performance 

requirements are similar, but are 

different from the FMVSS No. 122 test. 

UNECE Regulation No. 78 was 

developed 20 years ago in the United 

Kingdom to deal with problems in the 

field where the braking performance of 

motorcycles with exposed disc brakes 

was significantly reduced when ridden 

in heavy rain. This coincided with the 

large scale introduction of disc brakes 

on motorcycles. Therefore, in order to 

simulate heavy rain conditions, the 

UNECE Regulation No. 78 test requires 

a brake performance test with a wetted 

brake. This is achieved by spraying 


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Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 54029 

water directly onto the brakes during 

the test. The UNECE Regulation No. 78 

wet brake performance evaluation 

begins with a baseline test where each 

brake is tested separately and is 

required to decelerate a laden 

motorcycle at a specified rate, using the 

conditions of the dry stop test—single 

brake control actuated. For comparison, 

the same test is then repeated, but with 

a constant spray of water to wet the 

brakes. The difference in performance is 

evaluated immediately after the 

application of the respective brake, to 

ensure a minimum rise in deceleration 

performance with wet brakes. In 

addition, a drying brake can sometimes 

result in an excessively high pad 

friction leading to motorcycle instability 

and wheel lock; therefore a check for 

this ‘‘over recovery’’ is also included. 

As with the UNECE Regulation No. 

78/JSS 12–61 requirement, the current 

FMVSS No. 122 specifies an evaluation 

of wet brake performance by 

comparison of a baseline dry stop test 

result with performance after wetting. 

However, the philosophy behind the 

test is quite different, as the test is based 

on brake performance recovery 

following the motorcycle crossing an 

area of standing water. As such, the 

wetting procedure consists of immersing 

the front and rear brakes in water, 

separately, for two minutes each. 

Performance is evaluated with all brakes 

applied simultaneously and the wet 

brake recovery performance is based on 

the fifth stop after having immersed the 

brakes. The motorcycle is also tested in 

the lightly-loaded condition. Practical 

problems can occur when carrying out 

the brake immersion, due to low 

exhaust systems and other mechanical 

system locations, which may affect the 

motorcycle engine or transmission. 

The respective brake regulations 

address minimum performance 

requirements for wet brakes, albeit 

under different conditions. In terms of 

the overall performance requirements, 

the stringency comparison studies by 

NHTSA/Transport Canada and the 

industry both concluded that the 

UNECE Regulation No. 78 /JSS 12–61 

performance requirements are more 

stringent. During development of the 

GTR, it was agreed that the UNECE 

Regulation No. 78/JSS 12–61 procedure 

akin to braking while riding in the rain 

is a more common operating condition 

than crossing an area covered with 

water. Therefore, consistent with the 

GTR, the proposed wet brake test is 

based on the contents of the UNECE 

Regulation No. 78/JSS 12–61 test, and is 

applicable to all motorcycle categories. 

At present, the UNECE Regulation No. 

78/JSS 12–61 procedure excludes brakes 

that are fully enclosed because water is 

prevented from reaching the braking 

surface. For the purposes of the GTR, 

however, there was general agreement 

that the scope be expanded to include 

testing of enclosed disc brakes or drum 

brakes that have ventilation or 

inspection holes, as these include 

potential entry points for water spray. 

5. Heat Fade Test 

We propose to change the current 

FMVSS No. 122 heat fade test to the 

GTR heat fade test provision, which is 

based on the UNECE Regulation No. 78 

and JSS 12–61 fade test, because the 

results from both stringency studies 

indicated that the latter fade test is more 

stringent than the current FMVSS No. 

122 fade test. The heat fade test ensures 

that a minimum level of braking 

performance is maintained after 

numerous consecutive brake 

applications. In terms of real world 

conditions, this could be akin to 

frequent braking while driving in a busy 

suburban area or on a downhill 

gradient. Each of the current national 

regulations includes a test to evaluate 

the brake for heat fade and any change 

in brake performance. 

As with the wet brake test, the UNECE 

Regulation No. 78 and JSS 12–61 share 

the same test procedure and 

performance requirements. Each 

requires that the brakes be tested 

separately, with the motorcycle loaded 

to its maximum mass capacity. The 

FMVSS No. 122 test parameters are 

different in that all brakes are applied 

simultaneously and the motorcycle test 

mass is set at 200 pounds (90.7 kg) 

above the unloaded motorcycle mass 

(the 200 pounds includes the mass of 

the test rider and test equipment). 

Each test begins with a baseline test 

with an IBT between 55 °C and 100 °C, 

which provides the benchmark for 

performance comparison and evaluation 

of the heated brakes. This is followed by 

10 consecutive fade stops with the 

purpose of building heat within the 

brakes. The similarities between 

national regulations end here. In the 

UNECE Regulation No. 78/JSS 12–61, 

the final performance test occurs with 

one stop immediately following the 10 

fade stops. FMVSS No. 122 specifies an 

additional five recovery stops, and the 

performance in the fifth stop is 

compared to the baseline performance. 

The respective regulation test 

parameters include additional 

differences such as initial test speeds, 

brake lever and pedal control forces, 

deceleration rates, and the transmission 

gear selection (engine connected/ 

disconnected). Finally, to evaluate brake 

fade performance, the FMVSS No. 122 

procedure compares the brake pedal and 

lever actuation forces necessary to 

maintain the same deceleration as in the 

baseline test, whereas the UNECE 

Regulation No. 78/JSS 12–61 procedures 

compare deceleration (or stopping 

distance) for the same brake pedal and 

lever actuation forces as used in the 

baseline test. 

Although the national regulations 

have distinct differences, they share the 

common goal of evaluating the effect of 

heat on braking performance. The 

stringency of the respective tests was 

evaluated separately by the joint 

NHTSA and Transport Canada study, 

and by the industry. The results from 

both studies indicated that the UNECE 

Regulation No. 78/JSS 12–61 fade test 

was more stringent, thus providing the 

basis for the testing specifications of the 

GTR. 

Minor adjustments were made to the 

referenced national test procedure. In 

addition to the IBT adjustment, the text 

was revised to use the average brake 

control force from the baseline test, 

calculated from the measured values 

between 80 percent and 10 percent of 

the specified vehicle test speed. The 

brake heating procedure was also made 

more objective. UNECE Regulation No. 

78 presently requires that the 

motorcycle decelerate to the lesser of 3 

m/s2 or the maximum achievable 

deceleration rate with that brake 

control. For the purposes of the GTR, 

the latter performance requirement is 

made more objective by specifying that, 

at a minimum, the motorcycle meet the 

deceleration rate for the dry stop test— 

single brake control actuated, as noted 

in Table 2. 

The proposed fade test is applicable 

to motorcycle categories 3–3, 3–4 and 3– 

5, as is presently the case in the UNECE 

Regulation No. 78/JSS 12–61 and 

FMVSS No. 122. Only Canada’s national 

regulation, CMVSS No. 122, includes a 

fade test requirement for motorcycles 

with an engine size less than 50 cc and 

a top speed less than 50 km/h (i.e., 

motorcycle categories 3–1 and 3–2). 

However, during development of the 

GTR, none of the participants in the 

informal group could substantiate the 

need to include the fade test for those 

motorcycle categories. There was no 

negative experience reported due to the 

absence of a fade test for these smaller 

motorcycles, and therefore the GTR does 

not specify the heat fade test for such 

motorcycles. 

6. Parking Brake System Test 

The proposed parking brake test 

would improve upon the current 

FMVSS No. 122 parking brake system 

test by specifying a more stringent 


pwalker on PROD1PC71 with PROPOSALS2
54030 Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 

17ABS performance test reviews used in the 

drafting of GTR provisions will be posted in the 

docket. 

loading condition. The purpose of the 

parking brake system performance 

requirement is to ensure that 

motorcycles required to be equipped 

with parking brakes can remain 

stationary without rolling away when 

parked on an incline. 

The current FMVSS No. 122 specifies 

that the parking brake system be capable 

of holding the motorcycle stationary for 

five minutes when tested in the lightlyloaded condition on a 30 percent grade, 

in both the forward and reverse 

directions (to the limit of traction of the 

braked wheels). In addition, FMVSS No. 

122 requires that the parking brake be of 

a friction type with solely mechanical 

means to retain engagement. The 

parking brake requirements in UNECE 

Regulation No. 78/JSS 12–61 are 

equivalent and require that the brake 

must be capable of holding the 

motorcycle stationary on an 18 percent 

grade in the laden condition (i.e., the 

maximum weight limit specified by the 

manufacturer), in both the forward and 

reverse directions. No time limit is 

specified in either the UNECE or JSS 

regulation. 

The GTR uses the UNECE Regulation 

No. 78/JSS 12–61 parking brake test. 

The level of stringency appears to be 

similar to that in FMVSS No. 122, given 

the UNECE Regulation No. 78’s laden 

condition on an 18 percent grade versus 

the FMVSS No. 122’s lightly-loaded 

condition on a 30 percent grade. During 

development of the GTR, however, it 

was agreed that the laden condition is 

the worse case loading condition and 

test facilities around the world are more 

likely to have an 18 percent grade than 

a 30 percent grade available for testing. 

Consistent with the GTR, the 

proposed parking brake test includes a 

performance requirement that the 

motorcycle remain stationary for five 

minutes, which is present in current 

FMVSS No. 122. In addition, the GTR 

retains the common requirement that 

the parking brake system be designed to 

retain engagement solely by mechanical 

means, but not include the current 

FMVSS No. 122 requirement that the 

parking brake be of a friction type. This 

removes a design restriction and allows 

a manufacturer to use any parking brake 

system design that retains engagement 

by mechanical means. 

7. Antilock Brake System (ABS) 

Performance Test 

The current FMVSS No. 122 does not 

have any requirements for ABS 

performance. The proposed rule does 

not require ABS but does contain ABS 

performance requirements when such 

brake systems are present, to ensure 

minimum ABS performance in 

motorcycles that are so equipped. The 

purpose of the specified ABS test 

procedures is to assess the stability and 

stopping performance of a motorcycle 

with the ABS functioning. 

UNECE Regulation No. 78 and JSS 

12–61 include ABS-specific 

performance requirements but do not 

require that ABS be fitted on 

motorcycles. Common to both national 

regulations are wheel lock tests on highfriction and low-friction surfaces and an 

ABS failed systems performance test. In 

addition, the UNECE Regulation No. 78 

performance requirements include an 

ABS adhesion utilization (i.e., 

efficiency) test on high-friction and lowfriction surfaces, a high-friction surface 

to low-friction surface transition stop 

and a low-friction surface to highfriction surface transition stop. As 

mentioned above, current FMVSS No. 

122 does not include any ABS-specific 

performance requirements. 

The agency believes that the ABS 

definition developed for the GTR to 

upgrade FMVSS No. 122 is not as 

comprehensive as the ABS definition 

the agency uses in other Federal motor 

vehicle safety standards, FMVSS No. 

105, Hydraulic and Electric Brake 

Systems; FMVSS No. 121, Air Brake 

Systems; and FMVSS No. 135, Light 

Vehicle Brake Systems. However, we 

believe both definitions can be 

interpreted to mean the same thing. The 

two definitions are presented below: 

• GTR Definition: Antilock brake 

system or ABS means a system which 

senses wheel slip and automatically 

modulates the pressure producing the 

braking forces at the wheel(s) to limit 

the degree of wheel slip. 

• The current FMVSS Definition: 

Antilock brake system or ABS means a 

portion of a service brake system that 

automatically controls the degree of 

rotational wheel slip during braking by: 

(1) Sensing the rate of angular rotation 

of the wheels; 

(2) Transmitting signals regarding the 

rate of wheel angular rotation to one or 

more controlling devices which 

interpret those signals and generate 

responsive controlling output signals; 

and 

(3) Transmitting those controlling 

signals to one or more modulators 

which adjust brake actuating forces in 

response to those signals. 

The agency seeks comment on the 

proposed GTR definition and on the 

ABS definition used in the other braking 

standards. 

During the development of the GTR, 

each of the ABS performance tests and 

their corresponding requirements was 

reviewed to assess their appropriateness 

for the proposed motorcycle brake 

system GTR.17 With the exception of the 

ABS adhesion utilization test and the 

low-friction surface to high-friction 

surface transition stop, the Contracting 

Parties agreed to adopt, with selected 

revisions and clarifications, the 

remaining ABS test procedures and 

performance requirements. Possible 

alternatives for those tests on which 

agreement was not achieved are 

discussed further below. 

In the case of the wheel lock test on 

a low-friction surface, the present 

UNECE Regulation No. 78 states that for 

a road surface with a PBC less than or 

equal to 0.45, the specified initial test 

speed of 80 km/h may be reduced for 

safety reasons, but does not specify by 

how much. In order to ensure 

consistency in the way the motorcycles 

are evaluated and to achieve the 

objective of rider safety, the GTR and 

proposed rule specify that the test speed 

is the lesser of 0.8 Vmax or 60 km/h for 

the low-friction surface test. 

With regard to the low-friction to 

high-friction surface transition test, it 

was initially suggested that the 

motorcycle be evaluated while crossing 

from a wetted low-friction surface to a 

wetted high-friction surface (with a PBC 

exceeding 0.8). There was no reported 

issue in obtaining a wetted surface with 

a PBC exceeding 0.8 during the ABS 

validation tests. However, it was noted 

that there might be a problem in 

obtaining such a PBC on a wetted 

surface, and therefore the GTR removed 

all references to a wetted surface. 

Finally, when evaluating the 

performance of the ABS, the GTR 

specifies that the ABS be cycling 

throughout the respective tests. This 

means that the ABS is repeatedly 

modulating the brake force to prevent 

the directly controlled wheels from 

locking. Depending on the system, some 

brake feedback may be felt through the 

brake control, such that it is not possible 

to maintain the specified control force. 

Data obtained during the ABS validation 

tests revealed challenges while trying to 

maintain a consistent maximum brake 

control force, within the 20 percent 

range as initially proposed. Also, of the 

motorcycles tested, all ABS systems 

cycled at brake control actuation forces 

well below the proposed maximum 

limits. 

The GTR specifies that the test rider 

apply sufficient force to ensure that the 

ABS is fully cycling throughout the test. 

Two methodologies were considered to 

accomplish this result. The first was 

based on the tests in UNECE Regulation 


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Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 54031 

No. 78, in which minimum brake 

control actuation forces are specified, 

with the caveat that a higher force may 

be used if necessary to activate the ABS. 

In this case, it was agreed that 

stipulating minimum brake actuation 

forces was unnecessary; therefore the 

first method considered was simply to 

apply the necessary brake actuation 

force to activate the ABS. The second 

method considered specified maximum 

brake control actuation forces that 

cannot be exceeded. Unlike the first 

method, the second method was 

designed to ensure that all riders would 

have the benefit of the operation of ABS 

at or below specified maximum brake 

actuation forces, under the specified test 

conditions, and to facilitate verification 

testing. However, some cautioned that 

the latter method would also restrict 

design, which is not a desirable 

condition. 

Although the validation testing did 

provide important information toward 

setting maximum brake control 

actuation forces, there was concern that 

too few motorcycles were tested to 

allow setting fixed limits. Therefore, the 

GTR specifies the first method noted 

above. 

a. ABS Performance Test—Stopping 

Performance Requirement 

An adhesion utilization test is 

included in the UNECE regulation only, 

and compares the separate performance 

of the front and rear ABS brakes to the 

separate maximum braking performance 

of the front and rear brakes with the 

ABS disabled. It is evaluated on two 

road surfaces, a high-friction surface 

and a low-friction surface. 

Several discussions were held on the 

issues of test repeatability and 

variability of the results. The UNECE 

Regulation No. 78 test has a potential for 

producing less repeatable results 

because it is a test of the maximum 

motorcycle braking performance as 

achieved by the rider of the motorcycle. 

Numerous factors come into play when 

attempting to achieve maximum 

performance, including rider skill, the 

condition of the test equipment and site 

(tires, brakes and track surface), and the 

weather conditions. For example, the 

performance of ABS may be favorable 

when tested by a poorly performing 

rider; however, the efficiency of ABS 

can diminish significantly when tested 

by an expert rider. 

In conducting such tests, some ABS 

efficiency results were noted to exceed 

100 percent (i.e., improved deceleration 

compared to non-ABS braking 

performance), which can occur when 

the test rider is not able to achieve the 

maximum available deceleration rate. In 

addition to rider influence, we believe 

that the UNECE Regulation No. 78 

procedure is flawed in that it prescribes 

a constant control force for the entire 

stop. The available surface friction (i.e., 

peak braking coefficient, or PBC) 

increases as the motorcycle speed 

decreases, and thus the ABS system will 

have the advantage of higher 

deceleration rates at lower speeds. 

Therefore, to obtain the maximum 

deceleration capability without ABS, it 

is expected that the rider would have to 

increase the braking control force as the 

motorcycle is being decelerated. 

Safety and logistical issues were also 

noted with the UNECE Regulation No. 

78 adhesion utilization test: 

• Rider safety. The test requires that 

the rider achieve an impending lockedwheel braking condition with the ABS 

disabled, to obtain maximum 

deceleration data with which to 

evaluate ABS in later tests. This 

impending locked-wheel braking 

condition is at the beginning of loss-ofcontrol of the motorcycle, which could 

result in a crash. Even with protective 

outriggers in place, it is a hazardous 

condition that is asked of the test rider. 

• Logistical. The test requires 

modifying the brake system to disable 

the ABS. This may not be a simple task, 

or may not be possible depending on the 

complexity of the motorcycle brake 

system. Furthermore, the standard 

requires that maximum deceleration be 

recorded with an altered brake system 

(i.e., with disabled ABS), hence possibly 

outside the manufacturer’s design 

parameters. 

In light of these issues, alternate ABS 

tests were developed at the fourth 

informal group meeting in June 2005, 

based on the UNECE Regulation No. 78. 

The tests developed consisted of braking 

on both high- and low-friction surfaces 

with ABS cycling, but with emphasis 

placed on maintaining motorcycle 

stability rather than actual stopping 

performance. Nevertheless, the tests also 

specified stopping performance for the 

high-friction surface test only, based on 

the minimum performance requirements 

of the general UNECE Regulation No. 78 

dry stop test. The developed tests did 

not specify a stopping distance 

performance requirement for the lowfriction surface test, as there was no 

baseline test in UNECE Regulation No. 

78 with which to compare it. The tests 

neither required the brake system to be 

altered, nor the rider to attempt to 

obtain the maximum attainable 

deceleration rate, thereby addressing the 

safety and logistical issues. 

This alternate test was presented at 

the 58th GRRF in September 2005. 

While there was no issue raised with 

regard to the test procedure, the relative 

stringency of the stopping performance 

requirements was thought to be too low 

compared to the existing UNECE 

Regulation No. 78 ABS requirement, 

which could result in unnecessarily 

long stopping distances when ABS is 

cycling. 

The ABS test agreed on for the GTR 

and proposed here is conducted with all 

service brake controls actuated 

simultaneously, whereby brake and 

stability performance requirements are 

measured on low- and high-friction 

surfaces. The benefits of testing all 

service brake controls simultaneously 

include being able to compare the 

motorcycle ABS deceleration 

performance to the available PBC, 

without modification of the brake 

system and without rider influence. 

The brake performance requirement is 

based on the UNECE Regulation No. 78 

requirement that braking with the ABS 

cycling shall meet at least 70 percent of 

the maximum braking performance 

without ABS. Regarding stability during 

the ABS tests, the proposal defines 

wheel lock as the condition where the 

wheel attains 100 percent slip, and 

states in several of the performance 

requirements of the ABS tests that there 

must be no wheel lock. We are aware 

that momentary wheel lock at 100 

percent slip may occur during normal 

cycling of the ABS but note that it is 

difficult to establish a proposed time 

frame for such momentary lock-up 

duration. As a result, for the ABS tests, 

the regulatory text includes that wheel 

lock is allowed as long as the stability 

of the motorcycle is not affected to the 

extent that it requires the operator to 

release the control or causes the 

motorcycle to pass outside the test lane. 

Unlike the high-friction surface where 

measurement of PBC yields consistent 

results, PBC values can vary on the 

same low-friction, wetted surface. Given 

this characteristic, a range of PBC values 

is necessary for the low-friction ABS 

tests. Following the ABS validation 

tests, the proposed specification of a 

PBC range from 0.3 to 0.45 on a lowfriction surface was revised as none of 

the track surfaces on which the 

motorcycles were tested fell in this 

range. The GTR specifies that the track 

surface have a PBC less than or equal to 

0.45, and that the performance 

requirement is based on 70 percent of 

the track surface PBC at the time of 

testing. This is a more stringent 

requirement than previously considered 

in the development of the GTR’s ABS 

tests, whereby the performance 

requirement was based on a PBC of 0.3, 

even though the motorcycle could be 

tested on a surface with a PBC of 0.45. 


pwalker on PROD1PC71 with PROPOSALS2
54032 Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 

Braking performance in terms of 

stopping distance and deceleration for 

individually braked wheels was also 

considered. Maximum braking 

performance at each wheel is 

significantly affected by the motorcycle 

design. For example, different braking 

effectiveness is available through the 

rear wheel of a sport motorcycle 

compared to that of a cruiser 

motorcycle. Therefore, it is not possible 

to set constant maximum stopping 

distance or deceleration performance 

requirements for each wheel 

individually, for all motorcycle types. 

Given this, and that individual wheel 

braking performance is already covered 

in the dry stop test—single brake control 

actuated test, further testing for 

individually braked wheels is not 

considered necessary. In the event of a 

motorcycle with ABS installed on only 

one wheel, the test rider can still apply 

all service brake systems simultaneously 

as specified to meet the stability and 

stopping performance requirements. 

b. ABS Performance Test—Low-Friction 

to High-Friction Surface Transition Stop 

This is an existing test in UNECE 

Regulation No. 78, with the performance 

requirement that the motorcycle does 

not deviate from its initial course and 

that its deceleration shall rise to an 

‘‘appropriate’’ value in a ‘‘reasonable’’ 

time. To make the test more objective, 

actual performance values were 

incorporated in the GTR test to define 

what is appropriate and reasonable. 

At the fifth informal meeting in 

October 2005, Japan presented some 

preliminary test data that revealed a 

wide range of ABS performance 

responses to the sudden change in 

surface friction. Thus, at that time, it 

was not possible to determine a specific 

value that would be required to improve 

the objectivity of the UNECE test. The 

subsequent ABS validation tests 

provided additional insight in this 

regard, with a view to establishing 

specific performance requirements. In 

all cases, a rise in deceleration could be 

observed in a graphical depiction of the 

motorcycle deceleration over time, to 

various degrees. Regarding the response 

time to the change in surfaces, the 

actual test surfaces and the methods 

used to calculate the time interval 

varied sufficiently to make it difficult to 

define a time limit on the basis of the 

testing so far. Based on this data, the 

GTR introduced a limit of 1.0 seconds 

in order to match the current UNECE 

requirement that the deceleration 

should rise in a ‘‘reasonable time,’’ 

although there was very limited, 

confirmed technical support for such a 

figure. It was also agreed that when 

more data becomes available, these 

specifications could be reconsidered. 

Setting a minimum performance 

requirement to account for a rise in 

deceleration proved more difficult. 

Different criteria were applied to 

establish a method to objectively 

quantify changes in the deceleration 

rates before and after the transition 

point. Although each criterion yielded a 

rise in deceleration, the magnitude of 

the rise in the deceleration varied over 

time. This variation is related to the 

operating characteristics of the ABS as 

it cycles the brakes, which causes the 

motorcycle to slow at different 

deceleration rates throughout the stop. 

For the same motorcycle, ABS cycling 

can change depending on various 

factors including the available traction 

at that time, as interpreted by the 

hardware and software that comprises 

the ABS system. These provide 

sinusoidal-like deceleration signatures, 

before and after the transition point. As 

such, there is no a clear point where the 

deceleration can be shown to have 

increased. Rather, a segment of the 

deceleration data shall be analyzed, 

before and after the transition point, 

from which trends can be established to 

compare deceleration rates. 

In view of these findings, validation 

testing has demonstrated a need for 

further data analysis and possibly the 

testing of a larger sample of motorcycles 

to propose performance limits in terms 

of a minimum deceleration rate. In 

terms of quantifying a minimum rise in 

deceleration, the GTR keeps the 

performance requirement general, by 

stating that the deceleration shall 

increase after passing over the transition 

point. 

8. Partial Failure Test—Split Service 

Brake System 

The current FMVSS No. 122 partial 

failure test remains largely unchanged, 

except for a change in the terminology 

of applicability due to the newly 

proposed motorcycle categories. This is 

not a substantive change, as current 

FMVSS No. 122 indicates that the 

partial service brake system failure test 

‘‘do[es] not apply to a motor-driven 

cycle whose speed attainable in 1 mile 

is 30 m.p.h. or less,’’ and the proposed 

partial failure test specifications are not 

applicable to motorcycle categories 3–1 

and 3–2. Motorcycle categories 3–1 and 

3–2 are motorcycles with a maximum 

design speed not exceeding 50 km/h 

(31.1 mph). Thus, the proposed service 

brake system partial failure test is not 

substantially different from the current 

FMVSS No. 122 test. 

A motorcycle split service brake 

system is based on the passenger car 

brake system. Its use is unique to 

motorcycles in Canada and the United 

States. The purpose of this test is to 

ensure that, in the event of a pressure 

component leakage failure in one of the 

hydraulic subsystems, a minimum level 

of braking performance is still available 

in the remaining hydraulic subsystem to 

allow the rider to bring the motorcycle 

to a stop. FMVSS No. 122 is the only 

national regulation that addresses a 

failure test for motorcycles equipped 

with a split service brake system. 

9. Power-Assisted Braking System 

Failure Test 

The current FMVSS No. 122 does not 

have any performance requirements to 

test the failure of a power-assisted 

braking system. The proposed rule 

would not require power-assisted 

braking systems but does contain 

performance requirements for when 

such brake systems fail, to ensure 

minimum brake system performance in 

motorcycles that are so equipped. None 

of the world’s motorcycle brake 

regulations or standards currently 

include such a performance 

requirement, most likely because the 

application of power-assisted braking 

systems on motorcycles is relatively 

new. 

The GRRF recognized that some 

motorcycles are presently equipped 

with power-assisted braking systems, 

and that the use of such systems could 

expand in the future. Existing standards 

are limited to motor vehicles where this 

technology has been in use for many 

years, such as on passenger cars. At 

present, however, there is no known 

performance requirement in the event of 

the failure of a power-assisted braking 

system on a motorcycle. The GTR 

therefore specifies a test to ensure that, 

in the event of a power-assisted braking 

system failure, a minimum level of 

braking performance is still available to 

allow the rider to bring the motorcycle 

to a stop. Certifying to the performance 

requirement is not required if the 

motorcycle is equipped with another 

separate service brake system that 

operates without power-assist. 

In summary, the proposed test is 

based on the dry stop test—single brake 

control actuated (paragraph S6.3 of the 

proposed FMVSS No. 122), whereby the 

minimum performance requirement was 

initially set to that specified for the 

secondary brake system for motorcycles 

equipped with CBS. In developing the 

GTR, some believed this performance 

requirement was too low. For the 

revised version of the test, in the case 

of separate service brake systems, each 

brake control shall be tested separately 

and capable of meeting the minimum 


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brake performance for the single rear 

brake system. In the case of motorcycles 

equipped with CBS or a split service 

brake system, the proposed rule, 

consistent with the GTR, specifies 

testing of each brake control separately 

and the minimum performance 

requirements are those for the secondary 

brake system. 

C. Summary of Improvements 

This proposal, if made final, would 

improve the current FMVSS No. 122 

requirements and test procedures in 

several areas. First, it would make the 

dry brake test requirement more 

stringent by specifying testing of each 

service brake control individually with 

the motorcycle in the fully loaded 

condition (‘‘laden’’). Second, the 

proposal would establish a more 

stringent high speed test requirement by 

specifying a slightly higher rate of 

deceleration. Third, the proposal would 

replace the existing wet brake test with 

one that better simulates actual inservice conditions, by spraying water 

onto the brake disc instead of 

submerging the brake system before 

testing. Fourth, the proposal would 

specify an improved heat fade test based 

on European and Japanese national 

regulations, which share the same test 

procedure and performance 

requirements. Fifth, the proposal would 

mandate performance requirements for 

antilock brake systems when 

motorcycles are so equipped. Finally, 

the proposal would establish a new 

power-assisted braking system failure 

test requirement to evaluate the 

motorcycle’s performance in the event 

of a failure in the power-assisted 

braking system, if fitted. 

VI. Benefits, Costs, and the Proposed 

Compliance Date 

Although this proposal would add 

and update FMVSS No. 122 test 

procedures, we anticipate that virtually 

all motorcycles sold in the U.S. can 

meet the performance requirements as 

proposed, and thus, there is no 

measurable safety benefit derived from 

the proposal. However, NHTSA believes 

that the proposed performance 

requirements would help ensure the 

safety of motorcycle brake systems and 

thus have a beneficial effect on safety. 

The proposal includes several tests that 

would update and enhance performance 

requirements—tests both at the fully 

loaded condition (‘‘laden’’) and lightly 

loaded vehicle weight, which ensure 

adequate braking performance at the 

two extremes of the loading conditions; 

a wet brake test that is more 

representative of the manner in which 

brakes are wetted during real world 

riding in wet conditions; a variety of 

ABS performance tests, for motorcycles 

so equipped, to ensure adequate 

antilock performance during emergency 

braking or on slippery road conditions; 

and a new test in the event of a failure 

in the power-assisted braking system, if 

a motorcycle is so equipped. 

Moreover, as mentioned above, 

motorcycle manufacturers, and 

ultimately, consumers, both here and 

abroad, can expect to achieve cost 

savings through the formal 

harmonization of differing sets of 

standards when the Contracting Parties 

to the 1998 Global Agreement 

implement the Motorcycle Brake 

Systems GTR. Harmonization enables 

motorcycle manufacturers to test their 

models to just one regulation/series of 

tests to sell globally. 

We believe that although the proposal 

would add some new requirements to 

FMVSS No. 122 and replace some test 

procedures and performance 

requirements with ones based on more 

stringent standards used in another 

national regulation, none of the 

proposed tests would result in 

measurable costs to motorcycles. The 

proposal includes performance 

requirements that constitute the best 

practices from various standards and 

regulations. Some of the tests, such as 

the wet brake test, the ABS performance 

requirements, and the tests in the 

loaded condition, are an upgrade to the 

existing FMVSS No. 122. But current 

FMVSS No. 122 does not reflect the 

advancement of modern braking 

technologies, and motorcycles sold in 

the U.S. can virtually all meet the 

performance requirements as proposed 

without any major design changes. The 

agency believes that motorcycles sold in 

the U.S. market can comply with the 

requirements of ECE Regulation No. 78 

and JSS 12–61 without any 

modifications, and vice versa. As a 

result, any costs for design changes by 

motorcycle manufacturers to comply 

with the proposed performance 

requirements are expected to be 

negligible. Also, additional testing costs 

to comply with ABS performance 

requirements, if the motorcycle is 

equipped with ABS, are expected to be 

minimal. 

The agency has tentatively 

determined that virtually all of the 

current motorcycle fleet would comply 

with the proposal, if made final. 

Therefore, we are proposing to make the 

upgraded requirements mandatory at 

the beginning of the first September that 

is two full years after the publishing of 

a final rule. For example, if a final rule 

is adopted on December 1, 2009, 

compliance would be mandatory 

beginning September 1, 2012. Optional 

early compliance would be permitted on 

and after 30 days after the date of 

publication of a final rule in the Federal 

Register. 

VII. U.S. Selection of Options Within 

the GTR 

This NPRM fulfills our obligation to 

initiate domestic rulemaking to adopt 

the provisions of the GTR. The NPRM 

is based on the Motorcycle Brake 

Systems GTR. Certain provisions of the 

GTR contain options that Contracting 

Parties may select from when 

implementing the GTR into their 

national regulations. NHTSA’s 

specifications where there are options in 

the GTR are explained here: 

• We propose to specify that peak 

braking coefficient (PBC) be measured 

using the ASTM E1136 standard 

reference test tire, in accordance with 

ASTM Method E1337–90. In the GTR, 

the decision was made not to specify the 

method used to measure the coefficient 

of friction but leave it to the national 

regulations to choose which of two test 

methods enumerated in the GTR should 

be used to measure PBC. 

• We specify in high friction test 

surface conditions a PBC equal to 0.9 

instead of a ‘‘nominal’’ PBC of 0.9 to 

make the proposed test procedures more 

objective. 

• We propose that the initial brake 

temperature (IBT) be measured by plugtype thermocouples, as opposed to 

rubbing-type thermocouples. The two 

methods of measuring the IBT are 

included in the GTR and each 

Contracting Party must specify which 

temperature measurement it will use in 

its national regulation. 

• The GTR includes a requirement 

stating that the ‘‘brake linings shall not 

contain asbestos.’’ The GTR includes 

this requirement, which was adopted 

from UNECE Regulation No. 78, even 

though no test method or performance 

measure is included in the GTR to 

determine that the lining contains no 

asbestos. None of the brake standards in 

the Federal motor vehicle safety 

standards, including FMVSS 

No. 122, contain any requirement 

concerning the material of the brake 

lining. Concerns about asbestos relate to 

long-term environmental exposure. This 

is not within the scope of our 

rulemaking authority. Therefore, this 

NPRM does not include the proposal 

stating that ‘‘brake linings shall not 

contain asbestos.’’ 

• We propose adding a parenthetical 

to the GTR parking brake test that is 

present in current FMVSS No. 122 (see 

current S5.6, S7.9; proposed S6.8.3). In 

1978, NHTSA amended the FMVSS No. 


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122 parking brake test, clarifying that 

the test does not specify that a 

motorcycle be held on a 30 percent 

grade for 5 minutes if the limit of 

traction of its braked wheels is reached 

on a lower grade so that the motorcycle 

begins to slide (43 FR 46547, Oct. 10, 

1978). This amendment was based on an 

interpretation the agency provided in 

response to a petition for exemption by 

a company whose motorcycle’s limit of 

traction was reached on a 20 percent 

grade. The amendment had no effect 

upon the safety of the rule since it was 

a statement and clarification of an 

existing agency interpretation. A similar 

limit-of-traction provision exists with 

respect to the parking brake system 

performance requirements for 

hydraulically braked motorcycles 

(S5.2.1 of 49 CFR 571.105). 

• While most of the current tests in 

FMVSS No. 122 evaluate performance 

through stopping distance, the UNECE 

Regulation No. 78 and JSS 12–61 test 

methods allow brake performance to be 

measured through the use of either 

mean fully developed deceleration or 

stopping distance. While the GTR 

specifies performance requirements in 

reference to the respective national 

regulation on which the test was based, 

the performance tests proposed by 

NHTSA measure performance 

exclusively in stopping distance where 

applicable, to enhance enforceability of 

the Standard as opposed to providing 

optional performance measures. This is 

consistent with how performance 

requirements are stated in other Federal 

motor vehicle safety standards. This 

differs from the GTR in that our 

proposed performance tests do not 

allow manufacturers a choice to 

measure performance using either 

deceleration or stopping distance, but 

requires measurement of performance 

using stopping distance only where it is 

the applicable performance measure. 

The Executive Committee of the 1998 

Agreement and WP.29 are aware that 

the U.S. intended to make these choices 

as allowed in the GTR. We believe that 

the proposed provisions, if adopted, 

would improve motorcycle brake 

systems in the United States. 

VIII. Regulatory Analyses and Notices 

A. Vehicle Safety Act 

Under 49 U.S.C. Chapter 301, Motor 

Vehicle Safety (49 U.S.C. 30101 et seq.), 

the Secretary of Transportation is 

responsible for prescribing motor 

vehicle safety standards that are 

practicable, meet the need for motor 

vehicle safety, and are stated in 

objective terms. 49 U.S.C. 30111(a). 

When prescribing such standards, the 

Secretary must consider all relevant, 

available motor vehicle safety 

information. 49 U.S.C. 30111(b). The 

Secretary must also consider whether a 

proposed standard is reasonable, 

practicable, and appropriate for the type 

of motor vehicle or motor vehicle 

equipment for which it is prescribed 

and the extent to which the standard 

will further the statutory purpose of 

reducing traffic accidents and associated 

deaths. Id. Responsibility for 

promulgation of Federal motor vehicle 

safety standards was subsequently 

delegated to NHTSA. 49 U.S.C. 105 and 

§ 322; delegation of authority at 49 CFR 

1.50. 

The agency carefully considered these 

statutory requirements in proposing 

these amendments to FMVSS No. 122. 

We believe that the proposed 

amendments to FMVSS No. 122 are 

practicable. This document does not 

propose significant changes to the 

current performance requirements of 

FMVSS No. 122. Currently, we believe 

that all motorcycle brakes will pass the 

proposed tests. Additionally, if made 

final, the amendments would harmonize 

the U.S. requirements with the 

Motorcycle Brake Systems Global 

Technical Regulation. 

We believe that this proposed rule 

would be appropriate for the vehicles 

subject to the performance 

requirements. If adopted, the proposal 

would continue to exclude motorcycles 

for which the requirements and test 

procedures are impractical or 

unnecessary (e.g., low-speed 

motorcycles, categories 3–1 and 3–2, 

continue to be excluded from the heat 

fade test). 

Finally, the agency has tentatively 

concluded that the proposed 

amendments would provide objective 

procedures for determining compliance. 

The proposed test procedures have been 

evaluated by the agency, and we have 

tentatively concluded that they help 

achieve repeatable and reproducible 

results. Further, we are proposing test 

procedures to provide improved 

objectivity to existing performance 

requirements. 

B. Executive Order 12866 and DOT 

Regulatory Policies and Procedures 

NHTSA has considered the impacts of 

this rulemaking action under Executive 

Order 12866 and the Department of 

Transportation’s related policies and 

procedures. This rulemaking document 

was not reviewed by the Office of 

Management and Budget under E.O. 

12866. It is not considered to be 

significant under the Department’s 

Regulatory Policies and Procedures (44 

FR 11034, Feb. 26, 1979). This 

document proposes test procedures and 

performance requirements that would 

impose minimal additional costs on 

manufacturers, and is not expected to 

require design changes to current 

motorcycles. Given the minimal impacts 

of the proposed rule, we have not 

prepared a full regulatory evaluation. 

NHTSA does not anticipate direct 

safety benefits from this proposed rule. 

However, NHTSA believes that the 

proposed performance requirements 

would help ensure the safety of 

motorcycle brake systems and thus have 

a beneficial effect on safety. 

C. Executive Order 13132 (Federalism) 

Executive Order 13132 requires 

NHTSA to develop an accountable 

process to ensure ‘‘meaningful and 

timely input by State and local officials 

in the development of regulatory 

policies that have federalism 

implications.’’ ‘‘Policies that have 

federalism implications’’ is defined in 

the Executive Order to include 

regulations that have ‘‘substantial direct 

effects on the States, on the relationship 

between the national government and 

the States, or on the distribution of 

power and responsibilities among the 

various levels of government.’’ Under 

Executive Order 13132, the agency may 

not issue a regulation with Federalism 

implications, that imposes substantial 

direct compliance costs, and that is not 

required by statute, unless the Federal 

government provides the funds 

necessary to pay the direct compliance 

costs incurred by State and local 

governments, the agency consults with 

State and local governments, or the 

agency consults with State and local 

officials early in the process of 

developing the proposed regulation. 

NHTSA also may not issue a regulation 

with Federalism implications and that 

preempts State law unless the agency 

consults with State and local officials 

early in the process of developing the 

proposed regulation. 

NHTSA has examined today’s 

proposal pursuant to E.O. 13132 and 

concluded that no additional 

consultation with States, local 

governments or their representatives is 

mandated beyond the rulemaking 

process. The agency has concluded that 

the proposal does not have federalism 

implications because the rule does not 

have ‘‘substantial direct effects on the 

States, on the relationship between the 

national government and the States, or 

on the distribution of power and 

responsibilities among the various 

levels of government.’’ 

Further, no consultation is needed to 

discuss the preemptive effect of this 

NPRM. NHTSA rules can have 


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preemptive effect in at least two ways. 

First, the National Traffic and Motor 

Vehicle Safety Act contains an express 

preemption provision: ‘‘When a motor 

vehicle safety standard is in effect under 

this chapter, a State or a political 

subdivision of a State may prescribe or 

continue in effect a standard applicable 

to the same aspect of performance of a 

motor vehicle or motor vehicle 

equipment only if the standard is 

identical to the standard prescribed 

under this chapter.’’ 49 U.S.C. 

30103(b)(1). It is this statutory command 

that preempts State law, not today’s 

rulemaking, so consultation would be 

inappropriate. 

Second, in addition to the express 

preemption noted above, the Supreme 

Court has recognized that State 

requirements imposed on motor vehicle 

manufacturers, including sanctions 

imposed by State tort law, can stand as 

an obstacle to the accomplishment and 

execution of a NHTSA safety standard. 

When such a conflict is discerned, the 

Supremacy Clause of the Constitution 

makes the State requirements 

unenforceable. See Geier v. American 

Honda Motor Co., 529 U.S. 861 (2000). 

NHTSA has not discerned any potential 

State requirements in connection with 

the proposed rule, however, in part 

because such conflicts can arise in 

varied contexts. We cannot completely 

rule out the possibility that, if the 

proposal is adopted as a final rule, such 

a conflict might become apparent in the 

future through subsequent experience 

with the standard. NHTSA may opine 

on such conflicts in the future, if 

warranted. 

D. Executive Order 13045 

Executive Order 13045 (62 FR 19885, 

April 23, 1997) applies to any 

rulemaking that: (1) Is determined to be 

‘‘economically significant’’ as defined 

under E.O. 12866, and (2) concerns an 

environmental, health or safety risk that 

NHTSA has reason to believe may have 

a disproportionate effect on children. If 

the regulatory action meets both criteria, 

we must evaluate the environmental 

health or safety effects of the planned 

rule on children, and explain why the 

planned regulation is preferable to other 

potentially effective and reasonably 

feasible alternatives considered by us. 

This rulemaking is not subject to the 

Executive Order because it is not 

economically significant as defined in 

E.O. 12866. It also does not involve 

decisions based on health risks that 

disproportionately affect children. 

E. Executive Order 12988 (Civil Justice 

Reform) 

With respect to the review of the 

promulgation of a new regulation, 

section 3(b) of Executive Order 12988, 

‘‘Civil Justice Reform’’ (61 FR 4729, 

February 7, 1996), requires that 

Executive agencies make every 

reasonable effort to ensure that the 

regulation: (1) Specifies in clear 

language the preemptive effect; (2) 

specifies in clear language the effect on 

existing Federal law or regulation, 

including all provisions repealed, 

circumscribed, displaced, impaired, or 

modified; (3) provides a clear legal 

standard for affected conduct rather 

than a general standard, while 

promoting simplification and burden 

reduction; (4) specifies in clear language 

the retroactive effect; (5) specifies 

whether administrative proceedings are 

to be required before parties may file 

suit in court; (6) explicitly or implicitly 

defines key terms; and (7) addresses 

other important issues affecting clarity 

and general draftsmanship of 

regulations. This document is consistent 

with that requirement. 

Pursuant to this Order, NHTSA notes 

as follows. The preemptive effect of this 

proposed rule is discussed above. 

NHTSA notes further that there is no 

requirement that individuals submit a 

petition for reconsideration or pursue 

other administrative proceeding before 

they may file suit in court. 

F. Regulatory Flexibility Act 

Pursuant to the Regulatory Flexibility 

Act (5 U.S.C. 601 et seq., as amended by 

the Small Business Regulatory 

Enforcement Fairness Act (SBREFA) of 

1996) whenever an agency is required to 

publish a notice of rulemaking for any 

proposed or final rule, it must prepare 

and make available for public comment 

a regulatory flexibility analysis that 

describes the effect of the rule on small 

entities (i.e., small businesses, small 

organizations, and small governmental 

jurisdictions). However, no regulatory 

flexibility analysis is required if the 

head of an agency certifies the rule 

would not have a significant economic 

impact on a substantial number of small 

entities. The SBREFA amended the 

Regulatory Flexibility Act to require 

Federal agencies to provide a statement 

of the factual basis for certifying that a 

rule would not have a significant 

economic impact on a substantial 

number of small entities. 

We have considered the effects of this 

rulemaking action under the Regulatory 

Flexibility Act (5 U.S.C. 601 et seq.) and 

certify that this proposal would not 

have a significant economic impact on 

a substantial number of small entities. 

The agency is not currently aware of any 

motorcycle manufacturer that is 

considered a small business. The brake 

systems installed on motorcycles are 

typically developed by one of the major 

brake component suppliers, which are 

independent companies. There are cases 

where the motorcycle manufacturer may 

perform some of the brake system 

design and development in-house, and 

have the system components 

manufactured by an outside supplier. 

NHTSA does not consider any of these 

businesses to be small business entities 

that would be significantly 

economically impacted by this 

rulemaking. 

G. National Environmental Policy Act 

We have analyzed this proposed 

amendment for the purposes of the 

National Environmental Policy Act and 

determined that it would not have any 

significant impact on the quality of the 

human environment. 

H. Paperwork Reduction Act 

Under the Paperwork Reduction Act 

of 1995, a person is not required to 

respond to a collection of information 

by a Federal agency unless the 

collection displays a valid Office of 

Management and Budget (OMB) control 

number. The proposed rule does not 

contain any new information collection 

requirements. 

I. National Technology Transfer and 

Advancement Act 

Section 12(d) of the National 

Technology Transfer and Advancement 

Act of 1995 (NTTAA) (Pub. L. 104–113; 

15 U.S.C. 272) directs us to use 

voluntary consensus standards in 

regulatory activities unless doing so 

would be inconsistent with applicable 

law or otherwise impractical. Voluntary 

consensus standards are technical 

standards (e.g., materials specifications, 

test methods, sampling procedures, and 

business practices) that are developed or 

adopted by voluntary consensus 

standards bodies, such as the Society of 

Automotive Engineers (SAE) and the 

American Society for Testing and 

Materials (ASTM). The NTTAA directs 

us to provide Congress, through OMB, 

explanations when we decide not to use 

available and applicable voluntary 

consensus standards. 

ASTM E1136, Standard Specification 

for a Radial Standard Reference Test 

Tire, and ASTM Method E1337–90, 

Standard Test Method for Determining 

Longitudinal Peak Braking Coefficient of 

Paved Surfaces Using a Standard 

Reference Test Tire, are incorporated by 

reference in the regulatory text. This is 


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consistent with the NTTAA because 

these are industry voluntary consensus 

standards. NHTSA notes that the above 

ASTM standards are approved for 

incorporation by reference under 

571.500, Low-speed vehicles. 

J. Unfunded Mandates Reform Act 

Section 202 of the Unfunded 

Mandates Reform Act of 1995 (UMRA) 

requires Federal agencies to prepare a 

written assessment of the costs, benefits 

and other effects of proposed or final 

rules that include a Federal mandate 

likely to result in the expenditure by 

State, local or tribal governments, in the 

aggregate, or by the private sector, of 

more than $100 million in any one year 

(adjusted for inflation with base year of 

1995). Before promulgating a NHTSA 

rule for which a written statement is 

needed, section 205 of the UMRA 

generally requires us to identify and 

consider a reasonable number of 

regulatory alternatives and adopt the 

least costly, most cost-effective or least 

burdensome alternative that achieves 

the objectives of the rule. The 

provisions of section 205 do not apply 

when they are inconsistent with 

applicable law. Moreover, section 205 

allows us to adopt an alternative other 

than the least costly, most cost-effective 

or least burdensome alternative if we 

publish with the final rule an 

explanation why that alternative was 

not adopted. 

The proposed rule would not impose 

any unfunded mandates under the 

Unfunded Mandates Reform Act of 

1995. This rulemaking does not meet 

the definition of a Federal mandate 

because it would not result in costs of 

$100 million or more to either State, 

local, or tribal governments, in the 

aggregate, or to the private sector. Thus, 

this rulemaking is not subject to the 

requirements of sections 202 and 205 of 

the UMRA. 

K. Plain Language 

Executive Order 12866 requires each 

agency to write all rules in plain 

language. Application of the principles 

of plain language includes consideration 

of the following questions: 

• Have we organized the material to 

suit the public’s needs? 

• Are the requirements in the rule 

clearly stated? 

• Does the rule contain technical 

language or jargon that isn’t clear? 

• Would a different format (grouping 

and order of sections, use of headings, 

paragraphing) make the rule easier to 

understand? 

• Would more (but shorter) sections 

be better? 

• Could we improve clarity by adding 

tables, lists, or diagrams? 

• What else could we do to make the 

rule easier to understand? 

If you have any responses to these 

questions, please include them in your 

comments on this proposal. 

L. Regulation Identifier Number (RIN) 

The Department of Transportation 

assigns a regulation identifier number 

(RIN) to each regulatory action listed in 

the Unified Agenda of Federal 

Regulations. The Regulatory Information 

Service Center publishes the Unified 

Agenda in April and October of each 

year. You may use the RIN contained in 

the heading at the beginning of this 

document to find this action in the 

Unified Agenda. 

M. Privacy Act 

Anyone is able to search the 

electronic form of all comments 

received into any of our dockets by the 

name of the individual submitting the 

comment (or signing the comment, if 

submitted on behalf of an association, 

business, labor union, etc.). You may 

review DOT’s complete Privacy Act 

Statement in the Federal Register 

published on April 11, 2000 (65 FR 

19477 at 19478). 

IX. Public Participation 

How do I prepare and submit 

comments? 

Your comments must be written and 

in English. To ensure that your 

comments are correctly filed in the 

Docket, please include the docket 

number of this document in your 

comments. 

Your comments must not be more 

than 15 pages long. (49 CFR 553.21). We 

established this limit to encourage you 

to write your primary comments in a 

concise fashion. However, you may 

attach necessary additional documents 

to your comments. There is no limit on 

the length of the attachments. 

Please submit two copies of your 

comments, including the attachments, 

to the Docket Management Facility at 

the address given above under 

ADDRESSES. 

Comments may also be submitted to 

the docket electronically by logging onto 

the Federal eRulemaking Portal Web site 

at http://www.regulations.gov. Follow 

the online instructions for submitting 

comments. 

Please note that pursuant to the Data 

Quality Act, in order for substantive 

data to be relied upon and used by the 

agency, it must meet the information 

quality standards set forth in the OMB 

and DOT Data Quality Act guidelines. 

Accordingly, we encourage you to 

consult the guidelines in preparing your 

comments. OMB’s guidelines may be 

accessed at http://www.whitehouse.gov/ 

omb/fedreg/reproducible.html. DOT’s 

guidelines may be accessed at http:// 

dmses.dot.gov/submit/ 

DataQualityGuidelines.pdf. 

How can I be sure that my comments 

were received? 

If you wish Docket Management to 

notify you upon its receipt of your 

comments, enclose a self-addressed, 

stamped postcard in the envelope 

containing your comments. Upon 

receiving your comments, Docket 

Management will return the postcard by 

mail. 

How do I submit confidential business 

information? 

If you wish to submit any information 

under a claim of confidentiality, you 

should submit three copies of your 

complete submission, including the 

information you claim to be confidential 

business information, to the Chief 

Counsel, NHTSA, at the address given 

above under FOR FURTHER INFORMATION

CONTACT. In addition, you should 

submit two copies, from which you 

have deleted the claimed confidential 

business information, to the Docket 

Management Facility at the address 

given above under ADDRESSES. When 

you send a comment containing 

information claimed to be confidential 

business information, you should 

include a cover letter setting forth the 

information specified in our 

confidential business information 

regulation. (49 CFR Part 512.) 

Will the agency consider late 

comments? 

We will consider all comments that 

Docket Management receives before the 

close of business on the comment 

closing date indicated above under 

DATES. To the extent possible, we will 

also consider comments that Docket 

Management receives after that date. If 

Docket Management receives a comment 

too late for us to consider it in 

developing a final rule (assuming that 

one is issued), we will consider that 

comment as an informal suggestion for 

future rulemaking action. 

How can I read the comments submitted 

by other people? 

You may read the comments received 

by Docket Management at the address 

given above under ADDRESSES. The 

hours of the Docket are indicated above 

in the same location. You may also see 

the comments on the Internet. To read 

the comments on the Internet, go to 


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http://www.regulations.gov. Follow the 

online instructions for accessing the 

dockets. 

Please note that even after the 

comment closing date, we will continue 

to file relevant information in the 

Docket as it becomes available. Further, 

some people may submit late comments. 

Accordingly, we recommend that you 

periodically check the Docket for new 

material. 

List of Subjects in 49 CFR Part 571 

Motor vehicle safety, Reporting and 

record keeping requirements, Tires. 

In consideration of the foregoing, 

NHTSA proposes to amend 49 CFR 571 

as follows: 

PART 571—FEDERAL MOTOR 

VEHICLE SAFETY STANDARDS 

1. The authority citation for Part 571 

continues to read as follows: 

Authority: 49 U.S.C. 322, 30111, 30115, 

30117 and 30166; delegation of authority at 

49 CFR 1.50. 

2. Section 571.122 is revised to read 

as follows: 

§ 571.122 Standard No. 122; Motorcycle 

brake systems. 

S1. Scope. This standard specifies 

requirements for motorcycle service 

brake systems and, where applicable, 

associated parking brake systems. 

S2. Purpose. The purpose of the 

standard is to ensure safe motorcycle 

braking performance under normal and 

emergency riding conditions. 

S3. Application. This standard 

applies to motorcycles. 

S4. Definitions. 

Antilock brake system or ABS means 

a system which senses wheel slip and 

automatically modulates the pressure 

producing the braking forces at the 

wheel(s) to limit the degree of wheel 

slip. 

Baseline test means a stop or a series 

of stops carried out in order to confirm 

the performance of the brake prior to 

subjecting it to a further test such as the 

heating procedure or wet brake stop. 

Brake means those parts of the brake 

system where the forces opposing the 

movement of the motorcycle are 

developed. 

Brake system means the combination 

of parts consisting of the control, 

transmission, and brake, but excluding 

the engine, whose function it is to 

progressively reduce the speed of a 

moving motorcycle, bring it to a halt, 

and keep it stationary when halted. 

Category 3–1 motorcycle means a twowheeled motorcycle with an engine 

cylinder capacity in the case of a 

thermic engine not exceeding 50 cm3

and whatever the means of propulsion 

a maximum design speed not exceeding 

50 km/h. 

Category 3–2 motorcycle means a 

three-wheeled motorcycle of any wheel 

arrangement with an engine cylinder 

capacity in the case of a thermic engine 

not exceeding 50 cm3 and whatever the 

means of propulsion a maximum design 

speed not exceeding 50 km/h. 

Category 3–3 motorcycle means a twowheeled motorcycle with an engine 

cylinder capacity in the case of a 

thermic engine exceeding 50 cm3 or 

whatever the means of propulsion a 

maximum design speed exceeding 50 

km/h. 

Category 3–4 motorcycle means a 

motorcycle manufactured with three 

wheels asymmetrically arranged in 

relation to the longitudinal median 

plane with an engine cylinder capacity 

in the case of a thermic engine 

exceeding 50 cm3 or whatever the 

means of propulsion a maximum design 

speed exceeding 50 km/h. (This 

category definition is intended to 

include motorcycles with sidecars.) 

Category 3–5 motorcycle means a 

motorcycle manufactured with three 

wheels symmetrically arranged in 

relation to the longitudinal median 

plane with an engine cylinder capacity 

in the case of a thermic engine 

exceeding 50 cm3 or whatever the 

means of propulsion a maximum design 

speed exceeding 50 km/h. 

Combined brake system or CBS 

means: 

(a) For motorcycle categories 3–1 and 

3–3: a service brake system where at 

least two brakes on different wheels are 

actuated by the operation of a single 

control. 

(b) For motorcycle categories 3–2 and 

3–5: a service brake system where the 

brakes on all wheels are actuated by the 

operation of a single control. 

(c) For motorcycle category 3–4: a 

service brake system where the brakes 

on at least the front and rear wheels are 

actuated by the operation of a single 

control. (If the rear wheel and the 

asymmetrical wheel are braked by the 

same brake system, this is regarded as 

the rear brake.) 

Control means the part actuated 

directly by the rider in order to supply 

or control the energy required for 

braking the motorcycle to the 

transmission. 

Driver mass means the nominal mass 

of a driver that equals 75 kg (68 kg 

occupant mass plus 7 kg of luggage 

mass). 

Engine disconnected means when the 

engine is no longer connected to the 

driving wheel(s). 

Gross vehicle mass means the 

maximum mass of the fully laden solo 

vehicle, based on its construction and 

design performances, as declared by the 

manufacturer. 

Initial brake temperature means the 

temperature of the hottest brake before 

any brake application. 

Laden means the gross vehicle mass. 

Lightly loaded means mass in running 

order plus 15 kg for test equipment, or 

the laden condition, whichever is less. 

In the case of ABS tests on a low friction 

surface (paragraphs 4.9.4. to 4.9.7.), the 

mass for test equipment is increased to 

30 kg to account for outriggers. 

Mass in running order means the sum 

of unladen vehicle mass and driver 

mass. 

Peak braking coefficient or PBC 

means the measure of tire-to-road 

surface friction based on the maximum 

deceleration of a rolling tire. 

Power-assisted braking system means 

a brake system in which the energy 

necessary to produce the braking force 

is supplied by the physical effort of the 

rider assisted by one or more energy 

supplying devices, for example vacuum 

assisted (with vacuum booster). 

Secondary brake system means the 

second service brake system on a 

motorcycle equipped with a combined 

brake system. 

Service brake system means a brake 

system which is used for slowing the 

motorcycle when in motion. 

Sidecar means a one-wheeled vehicle 

that is attached to the side of a 

motorcycle. 

Single brake system means a brake 

system which acts on only one axle. 

Split service brake system or SSBS 

means a brake system that operates the 

brakes on all wheels, consisting of two 

or more subsystems actuated by a single 

control designed so that a single failure 

in any subsystem (such as a leakage type 

failure of a hydraulic subsystem) does 

not impair the operation of any other 

subsystem. 

Stopping distance means the distance 

traveled by the motorcycle from the 

point the rider begins to actuate the 

brake control to the point at which the 

motorcycle reaches full stop. For tests 

where simultaneous actuation of two 

controls is specified, the distance 

traveled is taken from the point the first 

control is actuated. 

Test speed means the motorcycle 

speed measured the moment the rider 

begins to actuate the brake control. For 

tests where simultaneous actuation of 

two controls is specified, the motorcycle 

speed is taken from the moment the first 

control is actuated. 

Transmission means the combination 

of components that provide the 


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54038 Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 

functional link between the control and 

the brake. 

Unladen vehicle mass means the 

nominal mass of a complete vehicle as 

determined by the following criteria: 

(a) Mass of the vehicle with bodywork 

and all factory fitted equipment, 

electrical and auxiliary equipment for 

normal operation of vehicle, including 

liquids, tools, fire extinguisher, standard 

spare parts, chocks and spare wheel, if 

fitted. 

(b) The fuel tanks filled to at least 90 

percent of rated capacity and the other 

liquid containing systems (except those 

for used water) to 100 percent of the 

capacity specified by the manufacturer. 

Vmax means either the speed 

attainable by accelerating at a maximum 

rate from a standing start for a distance 

of 1.6 km on a level surface, with the 

vehicle lightly loaded, or the speed 

measured in accordance with 

International Organization for 

Standardization (ISO) 7117:1995. 

Wheel lock means the condition that 

occurs when there is 100 percent wheel 

slip. 

S5. General requirements. 

S5.1 Brake system requirements. 

Each motorcycle shall meet each of the 

test requirements specified for a 

motorcycle of its type and for those 

brake features on the motorcycle. 

S5.1.1 Service brake system control 

operation. Each motorcycle shall have a 

configuration that enables a rider to 

actuate the service brake system control 

while seated in the normal driving 

position and with both hands on the 

steering control. 

S5.1.2 Secondary brake system 

control operation. Each motorcycle shall 

have a configuration that enables a rider 

to actuate the secondary brake system 

control while seated in the normal 

driving position and with at least one 

hand on the steering control. 

S5.1.3 Parking brake system. 

(a) If a parking brake system is fitted, 

it shall hold the motorcycle stationary 

on the slope prescribed in S6.8.2. The 

parking brake system shall: 

(1) have a control which is separate 

from the service brake system controls; 

and 

(2) be held in the locked position by 

solely mechanical means. 

(b) Each motorcycle equipped with a 

parking brake shall have a configuration 

that enables a rider to be able to actuate 

the parking brake system while seated 

in the normal driving position. 

S5.1.4 Two-wheeled motorcycles of 

categories 3–1 and 3–3. Each category 

3–1 and 3–3 two-wheeled motorcycle 

shall be equipped with either two 

separate service brake systems, or a split 

service brake system, with at least one 

brake operating on the front wheel and 

at least one brake operating on the rear 

wheel. 

S5.1.5 Three-wheeled motorcycles of 

category 3–4. Each category 3–4 

motorcycle shall comply with the brake 

system requirements in S5.1.4. A brake 

on the asymmetric wheel (with respect 

to the longitudinal axis) is not required. 

S5.1.6 Three-wheeled motorcycles of 

category 3–2. Each category 3–2 

motorcycle shall be equipped with a 

parking brake system plus one of the 

following service brake systems: 

(a) two separate service brake systems, 

except CBS, which, when applied 

together, operate the brakes on all 

wheels; or 

(b) a split service brake system; or 

(c) a CBS that operates the brake on 

all wheels and a secondary brake system 

which may be the parking brake system. 

S5.1.7 Three-wheeled motorcycles of 

categories 3–5. Each category 3–5 

motorcycle shall be equipped with: 

(a) a parking brake system; and 

(b) a foot actuated service brake 

system which operates the brakes on all 

wheels by way of either: 

(1) a split service brake system; or 

(2) a CBS and a secondary brake 

system, which may be the parking brake 

system. 

S5.1.8 Two separate service brake 

systems. For motorcycles where two 

separate service brake systems are 

installed, the systems may share a 

common brake, if a failure in one system 

does not affect the performance of the 

other. 

S5.1.9 Hydraulic service brake 

system. For motorcycles that use 

hydraulic fluid for brake force 

transmission, the master cylinder shall: 

(a) have a sealed, covered, separate 

reservoir for each brake system; and 

(b) have a minimum reservoir 

capacity equivalent to 1.5 times the total 

fluid displacement required to satisfy 

the new to fully worn lining condition 

with the worst case brake adjustment 

conditions; and 

(c) have a reservoir where the fluid 

level is visible for checking without 

removal of the cover. 

S5.1.10 Warning lamps. All warning 

lamps shall be mounted in the rider’s 

view. 

S5.1.10.1 Split service brake system 

warning lamps. 

(a) Each motorcycle that that is 

equipped with a split service brake 

system shall be fitted with a red 

warning lamp, which shall be activated: 

(1) When there is a hydraulic failure 

on the application of a force of ≤ 90 N 

on the control; or 

(2) without actuation of the brake 

control, when the brake fluid level in 

the master cylinder reservoir falls below 

the greater of: 

(i) that which is specified by the 

manufacturer; and 

(ii) that which is less than or equal to 

half of the fluid reservoir capacity. 

(b) To permit function checking, the 

warning lamp shall be illuminated by 

the activation of the ignition switch and 

shall be extinguished when the check 

has been completed. The warning lamp 

shall remain on while a failure 

condition exists whenever the ignition 

switch is in the ‘‘on’’ position. 

S5.1.10.2 Antilock brake system 

warning lamps. Each motorcycle 

equipped with an ABS system shall be 

fitted with a yellow warning lamp. The 

lamp shall be activated whenever there 

is a malfunction that affects the 

generation or transmission of signals in 

the motorcycle’s ABS system. To permit 

function checking, the warning lamp 

shall be illuminated by the activation of 

the ignition switch and extinguished 

when the check has been completed. 

The warning lamp shall remain on 

while a failure condition exists 

whenever the ignition switch is in the 

‘‘on’’ position. 

S5.2 Durability. 

S5.2.1 Compensation for wear. Wear 

of the brakes shall be compensated for 

by means of a system of automatic or 

manual adjustment. 

S5.2.2 Notice of wear. The friction 

material thickness shall either be visible 

without disassembly, or where the 

friction material is not visible, wear 

shall be assessed by means of a device 

designed for that purpose. 

S5.2.3 Testing. During all the tests in 

this standard and on their completion, 

there shall be no friction material 

detachment and no leakage of brake 

fluid. 

S5.3 Measurement of dynamic 

performance. There are two ways in 

which brake system performance is 

measured. The particular method to be 

used is specified in the respective tests 

in S6. 

S5.3.1 Stopping distance. 

(a) Based on the basic equations of 

motion: S = 0.1·V + (X)·V2, 

Where: 

S = stopping distance in meters 

V = initial vehicle speed in km/h 

X = a variable based on the requirement for 

each test 

(b) To calculate the corrected stopping 

distance using the actual vehicle test 

speed, the following formula is used: Ss 

= 0.1·Vs + (Sa ¥ 0.1·Va)·Vs2/Va2, 

Where: 

Ss = corrected stopping distance in meters 

Vs = specified vehicle test speed in km/h 

Sa = actual stopping distance in meters 

Va = actual vehicle test speed in km/h 


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Note to S5.3.1(b): This equation is only 

valid when the actual test speed (Va) is 

within ± 5 km/h of the specified test speed 

(Vs). 

S5.3.2 Continuous deceleration 

recording. The other method used to 

measure performance is the continuous 

recording of the vehicle instantaneous 

deceleration from the moment a force is 

applied to the brake control until the 

end of the stop. 

S6. Test conditions, procedures and 

performance requirements. 

S6.1 General. 

S6.1.1 Test surfaces. 

S6.1.1.1 High friction surface. A 

high friction surface is used for all 

dynamic brake tests excluding the ABS 

tests where a low-friction surface is 

specified. The high-friction surface test 

area is a clean, dry and level surface, 

with a gradient of ≤ 1 percent. The highfriction surface has a peak braking 

coefficient (PBC) of 0.9. 

S6.1.1.2 Low-friction surface. A lowfriction surface is used for ABS tests 

where a low-friction surface is specified. 

The low-friction surface test area is a 

clean and level surface, with a gradient 

of ≤ 1 percent. The low-friction surface 

has a PBC of ≤ 0.45. 

S6.1.1.3 Measurement of PBC. The 

PBC is measured using the American 

Society for Testing and Materials 

(ASTM) E1136–93 (Reapproved 2003) 

standard reference test tire, in 

accordance with ASTM Method E1337– 

90 (Reapproved 2002), at a speed of 40 

mph without water delivery. 

S6.1.1.4 Parking brake system tests. 

The specified test slope has a clean and 

dry surface that does not deform under 

the weight of the motorcycle. 

S6.1.1.5 Test lane width. For twowheeled motorcycles (motorcycle 

categories 3–1 and 3–3) the test lane 

width is 2.5 meters. For three-wheeled 

motorcycles (motorcycle categories 3–2, 

3–4 and 3–5) the test lane width is 2.5 

meters plus the vehicle width. 

S6.1.2 Ambient temperature. The 

ambient temperature is between 4 °C 

and 45 °C. 

S6.1.3 Wind speed. The wind speed 

is not more than 5 m/s. 

S6.1.4 Test speed tolerance. The 

test speed tolerance is ± 5 km/h. In the 

event of the actual test speed deviating 

from the specified test speed (but within 

the ± 5 km/h tolerance), the actual 

stopping distance is corrected using the 

formula in S5.3.2(b). 

S6.1.5 Automatic transmission. 

Motorcycles with automatic 

transmission shall meet all test 

requirements—whether they are for 

‘‘engine connected’’ or ‘‘engine 

disconnected.’’ If an automatic 

transmission has a neutral position, the 

neutral position is selected for tests 

where ‘‘engine disconnected’’ is 

specified. 

S6.1.6 Vehicle position and wheel 

lock. The vehicle is positioned in the 

center of the test lane for the beginning 

of each stop. Stops are made without the 

vehicle wheels passing outside the 

applicable test lane and without wheel 

lock. 

S6.1.7 Test sequence. Test sequence 

is as specified in Table 1. 

S6.2 Preparation. 

S6.2.1 Engine idle speed. The engine 

idle speed is set to the manufacturer’s 

specification. 

S6.2.2 Tire pressures. The tires are 

inflated to the manufacturer’s 

specification for the vehicle loading 

condition for the test. 

S6.2.3 Control application points 

and direction. For a hand control lever, 

the input force (F) is applied on the 

control lever’s forward surface 

perpendicular to the axis of the lever 

fulcrum and its outermost point on the 

plane along which the control lever 

rotates (see Figure 1). The input force is 

applied to a point located 50 

millimeters (mm) from the outermost 

point of the control lever, measured 

along the axis between the central axis 

of the fulcrum of the lever and its 

outermost point. For a foot control 

pedal, the input force is applied to the 

center of, and at right angles to, the 

control pedal. 

S6.2.4 Brake temperature 

measurement. The brake temperature is 

measured on the approximate center of 

the facing length and width of the most 

heavily loaded shoe or disc pad, one per 

brake, using a plug-type thermocouple 

that is embedded in the friction 

material, as shown in Figure 2. 

S6.2.5 Burnishing procedure. The 

vehicle brakes are burnished prior to 

evaluating performance. 

S6.2.5.1 Vehicle condition. 

(a) Vehicle lightly loaded. 

(b) Engine disconnected. 

S6.2.5.2 Conditions and procedure. 

(a) Initial brake temperature. Initial 

brake temperature before each brake 

application is ≤ 100 °C. 

(b) Test speed. 

(1) Initial speed: 50 km/h or 0.8 

Vmax, whichever is lower. 

(2) Final speed = 5 to 10 km/h. 

(c) Brake application. Each service 

brake system control actuated 

separately. 

(d) Vehicle deceleration. 

(1) Single front brake system only: 

(i) 3.0–3.5 m/s2 for motorcycle 

categories 3–3 and 3–5 

(ii) 1.5–2.0 m/s2 for motorcycle 

categories 3–1 and 3–2 

(2) Single rear brake system only: 1.5– 

2.0 m/s2

(3) CBS or split service brake system: 

3.5–4.0 m/s2

(e) Number of decelerations. There 

shall be 100 decelerations per brake 

system. 

(f) For the first stop, accelerate the 

vehicle to the initial speed and then 

actuate the brake control under the 

conditions specified until the final 

speed is reached. Then reaccelerate to 

the initial speed and maintain that 

speed until the brake temperature falls 

to the specified initial value. When 

these conditions are met, reapply the 

brake as specified. Repeat this 

procedure for the number of specified 

decelerations. After burnishing, adjust 

the brakes in accordance with the 

manufacturer’s recommendations. 

S6.3 Dry stop test—single brake 

control actuated. 

S6.3.1 Vehicle condition. 

(a) The test is applicable to all 

motorcycle categories. 

(b) Laden. For vehicles fitted with 

CBS and split service brake system, the 

vehicle is tested in the lightly loaded 

condition in addition to the laden 

condition. 

(c) Engine disconnected. 

S6.3.2 Test conditions and 

procedure. 

(a) Initial brake temperature. Initial 

brake temperature is ≥ 55 °C and ≤ 100 

°C. 

(b) Test speed. 

(1) Motorcycle categories 3–1 and 3– 

2: 40 km/h or 0.9 Vmax, whichever is 

lower. 

(2) Motorcycle categories 3–3, 3–4 and 

3–5: 60 km/h or 0.9 Vmax, whichever is 

lower. 

(c) Brake application. Each service 

brake system control actuated 

separately. 

(d) Brake actuation force. 

(1) Hand control: ≤ 200 N. 

(2) Foot control: 

(i) ≤ 350 N for motorcycle categories 

3–1, 3–2, 3–3 and 3–5. 

(ii) ≤ for motorcycle category 3–4. 

(e) Number of stops: until the vehicle 

meets the performance requirements, 

with a maximum of 6 stops. 

(f) For each stop, accelerate the 

vehicle to the test speed and then 

actuate the brake control under the 

conditions specified in this paragraph. 

S6.3.3 Performance requirements. 

When the brakes are tested in 

accordance with the test procedure set 

out in paragraph S6.3.2., the stopping 

distance shall be as specified in column 

2 of Table 2. 

S6.4 Dry stop test—all service brake 

controls actuated. 

S6.4.1 Vehicle condition. 

(a) The test is applicable to 

motorcycle categories 3–3, 3–4 and 3–5. 


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(b) Lightly loaded. 

(c) Engine disconnected. 

S6.4.2 Test conditions and 

procedure. 

(a) Initial brake temperature. Initial 

brake temperature is ≥ 55 °C and ≤ 100 

°C. 

(b) Test speed. Test speed is 100 km/ 

h or 0.9 Vmax, whichever is lower. 

(c) Brake application. Simultaneous 

actuation of both service brake system 

controls, if so equipped, or of the single 

service brake system control in the case 

of a service brake system that operates 

on all wheels. 

(d) Brake actuation force. 

(1) Hand control: ≤ 250 N. 

(2) Foot control: 

(i) ≤ 400 N for motorcycle categories 

3–3 and 3–5. 

(ii) ≤ 500 N for motorcycle category 3– 

4. 

(e) Number of stops: until the vehicle 

meets the performance requirements, 

with a maximum of 6 stops. 

(f) For each stop, accelerate the 

vehicle to the test speed and then 

actuate the brake control under the 

conditions specified in this paragraph. 

S6.4.3 Performance requirements. 

When the brakes are tested in 

accordance with the test procedure set 

out in paragraph S6.4.2., the stopping 

distance (S) shall be S ≤ 0.0060 V2

(where V is the specified test speed in 

km/h and S is the required stopping 

distance in meters). 

S6.5 High speed test. 

S6.5.1 Vehicle condition. 

(a) The test is applicable to 

motorcycle categories 3–3, 3–4 and 3–5. 

(b) Test is not required for vehicles 

with Vmax ≤ 125 km/h. 

(c) Lightly loaded. 

(d) Engine connected with the 

transmission in the highest gear. 

S6.5.2 Test conditions and 

procedure. 

(a) Initial brake temperature. Initial 

brake temperature is ≥ 55 °C and ≥ 100 

°C. 

(b) Test speed. 

(1) Test speed is 0.8 Vmax for 

motorcycles with Vmax > 125 km/h and 

< 200 km/h. 

(2) Test speed is 160 km/h for 

motorcycles with Vmax ≥ 200 km/h. 

(c) Brake application. Simultaneous 

actuation of both service brake system 

controls, if so equipped, or of the single 

service brake system control in the case 

of a service brake system that operates 

on all wheels. 

(d) Brake actuation force. 

(1) Hand control: ≤ 200 N. 

(2) Foot control: 

(i) ≤ 350 N for motorcycle categories 

3–3 and 3–5. 

(ii) ≤ 500 N for motorcycle category 3– 

4. 

(e) Number of stops: until the vehicle 

meets the performance requirements, 

with a maximum of 6 stops. 

(f) For each stop, accelerate the 

vehicle to the test speed and then 

actuate the brake control(s) under the 

conditions specified in this paragraph. 

S6.5.3 Performance requirements. 

When the brakes are tested in 

accordance with the test procedure set 

out in paragraph S6.5.2, the stopping 

distance (S) shall be ≤ 0.1 V + 0.0067 V2

(where V is the specified test speed in 

km/h and S is the required stopping 

distance in meters). 

S6.6 Wet brake test. 

S6.6.1 General information. 

(a) The test is comprised of two parts 

that are carried out consecutively for 

each brake system: 

(1) A baseline test based on the dry 

stop test—single brake control actuated 

(S6.3). 

(2) A single wet brake stop using the 

same test parameters as in (1), but with 

the brake(s) being continuously sprayed 

with water while the test is conducted 

in order to measure the brakes’ 

performance in wet conditions. 

(b) The test is not applicable to 

parking brake systems unless it is the 

secondary brake. 

(c) Drum brakes or fully enclosed disc 

brakes are excluded from this test unless 

ventilation or open inspection ports are 

present. 

(d) This test requires the vehicle to be 

fitted with instrumentation that gives a 

continuous recording of brake control 

force and vehicle deceleration. 

S6.6.2 Vehicle condition. 

(a) The test is applicable to all 

motorcycle categories. 

(b) Laden. For vehicles fitted with 

CBS and split service brake systems, the 

vehicle is tested in the lightly loaded 

condition in addition to the laden 

condition. 

(c) Engine disconnected. 

(d) Each brake is fitted with water 

spray equipment as shown in Figure 3. 

(1) Disc brakes—sketch of water spray 

equipment. The disc brake water spray 

equipment is installed as follows: 

(i) Water is sprayed onto each brake 

with a flow rate of 15 liters/hr. The 

water is equally distributed on each side 

of the rotor. 

(ii) If the surface of the rotor has any 

shielding, the spray is applied 45° prior 

to the shield. 

(iii) If it is not possible to locate the 

spray in the position shown on the 

sketch, or if the spray coincides with a 

brake ventilation hole or similar, the 

spray nozzle may be advanced by an 

additional 90° maximum from the edge 

of the pad, using the same radius. 

(2) Drum brakes with ventilation and 

open inspection ports. The water spray 

equipment is installed as follows: 

(i) Water is sprayed equally onto both 

sides of the drum brake assembly (on 

the stationary back plate and on the 

rotating drum) with a flow rate of 15 

liters/hr. 

(ii) The spray nozzles are positioned 

two-thirds of the distance from the outer 

circumference of the rotating drum to 

the wheel hub center. 

(iii) The nozzle position is > 15° from 

the edge of any opening in the drum 

back plate. 

S6.6.3 Baseline test—test conditions 

and procedure. 

(a) The test in paragraph S6.3 (dry 

stop test—single brake control actuated) 

is carried out for each brake system but 

with the brake control force that results 

in a vehicle deceleration of 2.5–3.0 m/ 

s2, and the following is determined: 

(1) The average brake control force 

measured when the vehicle is traveling 

between 80 percent and 10 percent of 

the specified test speed. 

(2) The average vehicle deceleration 

in the period 0.5 to 1.0 seconds after the 

point of actuation of the brake control. 

(3) The maximum vehicle 

deceleration during the complete stop 

but excluding the final 0.5 seconds. 

(b) Conduct 3 baseline stops and 

average the values obtained in (1), (2), 

and (3). 

S6.6.4 Wet brake test—test 

conditions and procedure. 

(a) The vehicle is ridden at the test 

speed used in the baseline test set out 

in S6.6.3 with the water spray 

equipment operating on the brake(s) to 

be tested and with no application of the 

brake system. 

(b) After a distance of ≥ 500 m, apply 

the average brake control force 

determined in the baseline test for the 

brake system being tested. 

(c) Measure the average vehicle 

deceleration in the period 0.5 to 1.0 

seconds after the point of actuation of 

the brake control. 

(d) Measure the maximum vehicle 

deceleration during the complete stop 

but excluding the final 0.5 seconds. 

S6.6.5 Performance requirements. 

When the brakes are tested in 

accordance with the test procedure set 

out in paragraph S6.6.4, the wet brake 

deceleration performance shall be: 

(a) The value measured in paragraph 

S6.6.4(c) shall be ≥ 60 percent of the 

average deceleration values recorded in 

the baseline test in paragraph 

S6.6.3(a)(2), i.e., in the period 0.5 to 1.0 

seconds after the point of actuation of 

the brake control; and 

(b) The value measured in S6.6.4(d) 

shall be ≤ 120 percent of the average 


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deceleration values recorded in the 

baseline test S6.6.3(a)(3), i.e., during the 

complete stop but excluding the final 

0.5 seconds. 

S6.7 Heat fade test. 

S6.7.1 General information. 

(a) The test comprises three parts that 

are carried out consecutively for each 

brake system: 

(1) A baseline test using the dry stop 

test—single brake control actuated 

(S6.3). 

(2) A heating procedure which 

consists of a series of repeated stops in 

order to heat the brake(s). 

(3) A hot brake stop using the dry stop 

test—single brake control actuated 

(S6.3), to measure the brake’s 

performance after the heating 

procedure. 

(b) The test is applicable to 

motorcycle categories 3–3, 3–4 and 3–5. 

(c) The test is not applicable to 

parking brake systems and secondary 

service brake systems. 

(d) All stops are carried out with the 

motorcycle laden. 

(e) The heating procedure requires the 

motorcycle to be fitted with 

instrumentation that gives a continuous 

recording of brake control force and 

vehicle deceleration. 

S6.7.2 Baseline test. 

S6.7.2.1 Vehicle condition—baseline 

test. Engine disconnected. 

S6.7.2.2 Test conditions and 

procedure—baseline test. 

(a) Initial brake temperature. Initial 

brake temperature is ≥ 55 °C and ≤ 100 

°C. 

(b) Test speed. Test speed is 60 km/ 

h or 0.9 Vmax, whichever is the lower. 

(c) Brake application. Each service 

brake system control is actuated 

separately. 

(d) Brake actuation force. 

(1) Hand control: ≤ 200 N. 

(2) Foot control: 

(i) ≤ 350 N for motorcycle categories 

3–3 and 3–5. 

(ii) ≤ 500 N for motorcycle category 3– 

4. 

(e) Accelerate the vehicle to the test 

speed, actuate the brake control under 

the conditions specified and record the 

control force required to achieve the 

vehicle braking performance specified 

in the table to S6.3.3 (Table 2). 

S6.7.3 Heating procedure. 

S6.7.3.1 Vehicle condition—heating 

procedure. Engine transmission: 

(a) From the specified test speed to 50 

percent specified test speed: connected, 

with the highest appropriate gear 

selected such that the engine speed 

remains above the manufacturer’s 

specified idle speed. 

(b) From 50 percent specified test 

speed to standstill: disconnected. 

S6.7.3.2 Test conditions and 

procedure—heating procedure. 

(a) Initial brake temperature. Initial 

brake temperature is (prior to first stop 

only) ≥ 55° C and ≤ 100 °C. 

(b) Test speed. 

(1) Single brake system, front wheel 

braking only: 100 km/h or 0.7 Vmax, 

whichever is the lower. 

(2) Single brake system, rear wheel 

braking only: 80 km/h or 0.7 Vmax, 

whichever is the lower. 

(3) CBS or split service brake system: 

100 km/h or 0.7 Vmax, whichever is the 

lower. 

(c) Brake application. Each service 

brake system control actuated 

separately. 

(d) Brake actuation force. 

(1) For the first stop: The constant 

control force that achieves a vehicle 

deceleration rate of 3.0–3.5 m/s2 while 

the vehicle is decelerating between 80 

percent and 10 percent of the specified 

speed. 

(2) For the remaining stops: 

(i) The same constant brake control 

force as used for the first stop. 

(ii) Number of stops: 10. 

(iii) Interval between stops: 1000 m. 

(e) Carry out a stop to the conditions 

specified in this paragraph and then 

immediately use maximum acceleration 

to reach the specified speed and 

maintain that speed until the next stop 

is made. 

S6.7.4 Hot brake stop—test 

conditions and procedure. Perform a 

single stop under the conditions used in 

the baseline test (S6.7.2) for the brake 

system that has been heated during the 

procedure in accordance with S6.7.3. 

This stop is carried out within one 

minute of the completion of the 

procedure set out in S6.7.3 with a brake 

control application force less than or 

equal to the force used during the test 

set out in S6.7.2. 

S6.7.5 Performance requirements. 

When the brakes are tested in 

accordance with the test procedure set 

out in S6.7.4, the stopping distance S2

shall be ≤ 1.67 S1¥ 0.67 × 0.1V, 

Where: 

S1 = corrected stopping distance in meters 

achieved in the baseline test set out in 

S6.7.2. 

S2 = corrected stopping distance in meters 

achieved in the hot brake stop set out in 

S6.7.4. 

V = specified test speed in km/h. 

S6.8 Parking brake system test—for 

motorcycles with parking brakes. 

S6.8.1 Vehicle condition. 

(a) The test is applicable to 

motorcycle categories 3–2, 3–4 and 3–5. 

(b) Laden. 

(c) Engine disconnected. 

S6.8.2 Test conditions and 

procedure. 

(a) Initial brake temperature. Initial 

brake temperature is ≤ 100 °C. 

(b) Test surface gradient. Test surface 

gradient is equal to 18 percent. 

(c) Brake actuation force. 

(1) Hand control: ≤ 400 N. 

(2) Foot control: ≤ 500 N. 

(d) For the first part of the test, park 

the vehicle on the test surface gradient 

facing up the slope by applying the 

parking brake system under the 

conditions specified in this paragraph. If 

the vehicle remains stationary, start the 

measurement of the test period. 

(e) On completion of the test with 

vehicle facing up the gradient, repeat 

the same test procedure with the vehicle 

facing down the gradient. 

S6.8.3 Performance requirements. 

When tested in accordance with the test 

procedure set out in S6.8.2, the parking 

brake system shall hold the vehicle 

stationary (to the limits of traction of the 

braked wheels) for 5 minutes when the 

vehicle is both facing up and facing 

down the gradient. 

S6.9 ABS tests. 

S6.9.1 General. 

(a) The tests are only applicable to the 

ABS fitted on motorcycle categories 3– 

1 and 3–3. 

(b) The tests are to confirm the 

performance of brake systems equipped 

with ABS and their performance in the 

event of ABS electrical failure. 

(c) Fully cycling means that the antilock system is repeatedly modulating 

the brake force to prevent the directly 

controlled wheels from locking. 

(d) Wheel-lock is allowed as long as 

the stability of the vehicle is not affected 

to the extent that it requires the operator 

to release the control or causes a vehicle 

wheel to pass outside the test lane. 

(e) The test series comprises the 

individual tests in Table 3, which may 

be carried out in any order. 

S6.9.2 Vehicle condition. 

(a) Lightly loaded. 

(b) Engine disconnected. 

S6.9.3 Stops on a high-friction 

surface. 

S6.9.3.1 Test conditions and 

procedure. 

(a) Initial brake temperature. Initial 

brake temperature is ≥ 55 °C and ≤ 100 

°C. 

(b) Test speed. Test speed is 60 km/ 

h or 0.9 Vmax, whichever is lower. 

(c) Brake application. Simultaneous 

actuation of both service brake system 

controls, if so equipped, or of the single 

service brake control in the case of a 

service brake system that operates on all 

wheels. 

(d) Brake actuation force. The force 

applied is that which is necessary to 

ensure that the ABS will cycle fully 

throughout each stop, down to 10 km/ 

h. 


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(e) If one wheel is not equipped with 

ABS, the control for the service brake on 

that wheel is actuated with a force that 

is lower than the force that will cause 

the wheel to lock. 

(f) Number of stops: until the vehicle 

meets the performance requirements, 

with a maximum of 6 stops. 

(g) For each stop, accelerate the 

vehicle to the test speed and then 

actuate the brake control under the 

conditions specified in this paragraph. 

S6.9.3.2 Performance requirements. 

When the brakes are tested in 

accordance with the test procedures 

referred to in S6.9.3.1: 

(a) the stopping distance (S) shall be 

≤ 0.0063V 2 (where V is the specified 

test speed in km/h and S is the required 

stopping distance in meters); and 

(b) there shall be no wheel lock and 

the vehicle wheels shall stay within the 

test lane. 

S6.9.4 Stops on a low friction 

surface. 

S6.9.4.1 Test conditions and 

procedure. As set out in S6.9.3.1, but 

using the low friction surface instead of 

the high friction one. 

S6.9.4.2 Performance requirements. 

When the brakes are tested in 

accordance with the test procedures set 

out in S6.9.4.1: 

(a) the stopping distance (S) shall be 

≤ 0.0056 V 2/P (where V is the specified 

test speed in km/h, P is the peak braking 

coefficient and S is the required 

stopping distance in meters); and 

(b) there shall be no wheel lock and 

the vehicle wheels shall stay within the 

test lane. 

S6.9.5 Wheel lock checks on high 

and low friction surfaces. 

S6.9.5.1 Test conditions and 

procedure. 

(a) Test surfaces. 

(b) Initial brake temperature. Initial 

brake temperature is ≥ 55 °C and ≤ 100 

°C. 

(c) Test speed. 

(1) On the high friction surface: 80 

km/h or 0.8 Vmax, whichever is lower. 

(2) On the low friction surface: 60 km/ 

h or 0.8 Vmax, whichever is lower. 

(d) Brake application. 

(1) Each service brake system control 

actuated separately. 

(2) Where ABS is fitted to both brake 

systems, simultaneous actuation of both 

brake controls in addition to (1). 

(e) Brake actuation force. The force 

applied is that which is necessary to 

ensure that the ABS will cycle fully 

throughout each stop, down to 10 km/ 

h. 

(f) Brake application rate. The brake 

control actuation force is applied in 0.2– 

0.5 seconds. 

(g) Number of stops: until the vehicle 

meets the performance requirements, 

with a maximum of 3 stops. 

(h) For each stop, accelerate the 

vehicle to the test speed and then 

actuate the brake control under the 

conditions specified in this paragraph. 

S6.9.5.2 Performance requirements. 

When the brakes are tested in 

accordance with the test procedures set 

out in S6.9.5.1, there shall be no wheel 

lock and the vehicle wheels shall stay 

within the test lane. 

S6.9.6 Wheel lock check—high to 

low friction surface transition. 

S6.9.6.1 Test conditions and 

procedure. 

(a) Test surfaces. A high friction 

surface immediately followed by a low 

friction surface. 

(b) Initial brake temperature. Initial 

brake temperature is ≥ 55 °C and ≤ 100 

°C. 

(c) Test speed. The speed that will 

result in 50 km/h or 0.5 Vmax, 

whichever is the lower, at the point 

where the vehicle passes from the high 

friction to the low friction surface. 

(d) Brake application. 

(1) Each service brake system control 

actuated separately. 

(2) Where ABS is fitted to both brake 

systems, simultaneous actuation of both 

brake controls in addition to (1). 

(e) Brake actuation force. The force 

applied is that which is necessary to 

ensure that the ABS will cycle fully 

throughout each stop, down to 10 km/ 

h. 

(f) Number of stops: until the vehicle 

meets the performance requirements, 

with a maximum of 3 stops. 

(g) For each stop, accelerate the 

vehicle to the test speed and then 

actuate the brake control before the 

vehicle reaches the transition from one 

friction surface to the other. 

S6.9.6.2 Performance requirements. 

When the brakes are tested in 

accordance with the test procedures set 

out in S6.9.6.1, there shall be no wheel 

lock and the vehicle wheels shall stay 

within the test lane. 

S6.9.7 Wheel lock check—low to 

high friction surface transition. 

S6.9.7.1 Test conditions and 

procedure. 

(a) Test surfaces. A low friction 

surface immediately followed by a high 

friction surface with a PBC ≥ 0.8. 

(b) Initial brake temperature. Initial 

brake temperature is ≥ 55 °C and ≤ 100 

°C. 

(c) Test speed. The speed that will 

result in 50 km/h or 0.5 Vmax, 

whichever is the lower, at the point 

where the vehicle passes from the low 

friction to the high friction surface. 

(d) Brake application. 

(1) Each service brake system control 

applied separately. 

(2) Where ABS is fitted to both brake 

systems, simultaneous application of 

both brake controls in addition to (1). 

(e) Brake actuation force. The force 

applied is that which is necessary to 

ensure that the ABS will cycle fully 

throughout each stop, down to 10 km/ 

h. 

(f) Number of stops: until the vehicle 

meets the performance requirements, 

with a maximum of 3 stops. 

(g) For each stop, accelerate the 

vehicle to the test speed and then 

actuate the brake control before the 

vehicle reaches the transition from one 

friction surface to the other. 

(h) Record the vehicle’s continuous 

deceleration. 

S6.9.7.2 Performance requirements. 

When the brakes are tested in 

accordance with the test procedures set 

out in S6.9.7.1: 

(a) there shall be no wheel lock and 

the vehicle wheels shall stay within the 

test lane, and 

(b) within 1 second of the rear wheel 

passing the transition point between the 

low and high friction surfaces, the 

vehicle deceleration shall increase. 

S6.9.8 Stops with an ABS electrical 

failure. 

S6.9.8.1 Test conditions and 

procedure. With the ABS electrical 

system disabled, carry out the test set 

out in S6.3 (dry stop test—single brake 

control actuated) applying the 

conditions relevant to the brake system 

and vehicle being tested. 

S6.9.8.2 Performance requirements. 

When the brakes are tested in 

accordance with the test procedure set 

out in S6.9.8.1: 

(a) the system shall comply with the 

failure warning requirements of 

S5.1.10.2; and 

(b) the minimum requirements for 

stopping distance shall be as specified 

in column 2 under the heading ‘‘Single 

brake system, rear wheel(s) braking 

only’’ in Table 2. 

S6.10 Partial failure test—for split 

service brake systems. 

S6.10.1 General information. 

(a) The test is only applicable to 

vehicles that are equipped with split 

service brake systems. 

(b) The test is to confirm the 

performance of the remaining subsystem 

in the event of a hydraulic system 

leakage failure. 

S6.10.2 Vehicle condition. 

(a) The test is applicable to 

motorcycle categories 3–3, 3–4 and 3–5. 

(b) Lightly loaded. 

(c) Engine disconnected. 

S6.10.3 Test conditions and 

procedure. 


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(a) Initial brake temperature. Initial 

brake temperature is ≥ 55 °C and ≤ 100 

°C. 

(b) Test speed. Test speed is 50 km/ 

h and 100 km/h or 0.8 Vmax, whichever 

is lower. 

(c) Brake actuation force. 

(1) Hand control: ≤ 250 N. 

(2) Foot control: ≤ 400 N. 

(d) Number of stops: until the vehicle 

meets the performance requirements, 

with a maximum of 6 stops for each test 

speed. 

(e) Alter the service brake system to 

induce a complete loss of braking in any 

one subsystem. Then, for each stop, 

accelerate the vehicle to the test speed 

and then actuate the brake control under 

the conditions specified in this 

paragraph. 

(f) Repeat the test for each subsystem. 

S6.10.4 Performance requirements. 

When the brakes are tested in 

accordance with the test procedure set 

out in S6.10.3: 

(a) The system shall comply with the 

failure warning requirements set out in 

paragraph 3.1.11.; and 

(b) The stopping distance (S) shall be 

≤ 0.1 V + 0.0117 V2 (where V is the 

specified test speed in km/h and S is the 

required stopping distance in meters). 

S6.11 Power-assisted braking system 

failure test. 

S6.11.1 General information. 

(a) The test is not conducted when the 

vehicle is equipped with another 

separate service brake system. 

(b) The test is to confirm the 

performance of the service brake system 

in the event of failure of the power 

assistance. 

S6.11.2 Test conditions and 

procedure. Carry out the test set out in 

S6.3.3 (dry stop test—single brake 

control actuated) for each service brake 

system with the power assistance 

disabled. 

S6.11.3 Performance requirements. 

When the brakes are tested in 

accordance with the test procedure set 

out in S6.11.2, the stopping distance 

shall be as specified in column 2 of 

Table 4. Note that if the power 

assistance may be activated by more 

than one control, the above performance 

shall be achieved when each control is 

actuated separately. 

BILLING CODE 4910–59–P 


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Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 54045 


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Federal Register / Vol. 73, No. 181 / Wednesday, September 17, 2008 / Proposed Rules 54047 

Issued on: September 10, 2008. 

Stephen R. Kratzke, 

Associate Administrator for Rulemaking. 

[FR Doc. E8–21568 Filed 9–16–08; 8:45 am] 

BILLING CODE 4910–59–C 


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