[Federal Register Volume 73, Number 181 (Wednesday, September 17, 2008)]
[Proposed Rules]
[Pages 54020-54047]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E8-21568]



[[Page 54019]]

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Part IV





Department of Transportation





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National Highway Traffic Safety Administration



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49 CFR Part 571



Federal Motor Vehicle Safety Standards; Motorcycle Brake Systems; 
Proposed Rule

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

[[Page 54020]]


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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).

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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 in-service 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:
    <bullet> Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the online instructions for submitting 
comments.
    <bullet> 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.
    <bullet> 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.
    <bullet> 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: 
<a href="/cdn-cgi/l/email-protection#6304060c1104064d100c0c070c0c23070c174d040c15"><span class="__cf_email__" data-cfemail="6e090b011c090b401d01010a01012e0a011a40090118">[email protected]</span></a>) (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: <a href="/cdn-cgi/l/email-protection#fb9e819a959ad58c94959f9296959e93bb9f948fd59c948d"><span class="__cf_email__" data-cfemail="30554a515e511e475f5e54595d5e555870545f441e575f46">[email protected]</span></a>) (Telephone: 
(202) 366-0846) (Fax: (202) 493-2290).
    For legal issues: Ms. Sarah Alves, Office of the Chief Counsel 
(NCC-112) (E-mail: <a href="/cdn-cgi/l/email-protection#ec9f8d9e8d84c28d809a899fac888398c28b839a"><span class="__cf_email__" data-cfemail="becddfccdfd690dfd2c8dbcdfedad1ca90d9d1c8">[email protected]</span></a>) (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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    \1\ See U.S. Department of Transportation, ``Action Plan to 
Reduce Motorcycle Fatalities,'' at 8 (October 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'').

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    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.
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    \2\ The 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.
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    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.
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    \3\ While 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.
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    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 power-
assisted 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\
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    \4\ ``Action Plan to Reduce Motorcycle Fatalities,'' supra note 
1, at 8.
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    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,

[[Page 54022]]

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\
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    \5\ See Brake Systems on Motorcycles Proposed Motor Vehicle 
Safety Standard, 36 FR 5516 (Mar. 24, 1971).
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    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 two-wheeled 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 pre- and 
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, three-wheeled 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 (fps\2\). 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 pre-burnish 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 fps\2\. As a check test, three 
baseline stops \6\ are conducted from 30 mph at 10 to 11 fps\2\, 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 fps\2\, 
followed immediately by five fade recovery stops from 30 mph at a 
deceleration rate of 10 to 11 fps\2\. 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.
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    \6\ The 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.
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    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 fps\2\, 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 fps\2\. 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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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.
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    \7\ The 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 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.
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    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:
    <bullet> UNECE Regulation No. 78--Uniform provisions concerning the 
approval of vehicles of category L with regard to braking.
    <bullet> FMVSS No.122, Motorcycle brake systems.
    <bullet> Canada Motor Vehicle Safety Regulation No. 122--Motorcycle 
brake systems. (CMVSS No. 122).

    Note: FMVSS and CMVSS No. 122 are substantially similar.

    <bullet> Japan Safety Standard JSS12-61.
    <bullet> Australian Design Rule 33/00--Brake systems for 
motorcycles and mopeds.
    <bullet> International Organization for Standardization (ISO) 
8710:1995, Motorcycles--Brakes and braking devices--tests and 
measurement methods.
    <bullet> ISO 12364:2001, Two-wheeled motorcycles--Antilock braking 
systems (ABS)--tests and measurement methods.
    <bullet> 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.
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    \8\ The 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.
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    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:
    <bullet> Burnish procedure (FMVSS No. 122)
    <bullet> Dry stop test with each service brake control actuated 
separately (UNECE Regulation No. 78/JSS 12-61)
    <bullet> Dry stop test with all service brake systems applied 
simultaneously (FMVSS No. 122)
    <bullet> High speed test (JSS 12-61)
    <bullet> Wet brake test (UNECE Regulation No. 78/JSS 12-61)
    <bullet> Heat fade test (UNECE Regulation No. 78/JSS 12-61)
    <bullet> Parking brake test (UNECE Regulation No. 78/JSS 12-61)
    <bullet> ABS tests (UNECE Regulation No. 78/JSS 12-61)
    <bullet> Partial failure test--split service brake systems (FMVSS 
No. 122)
    <bullet> 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.
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    \9\ See http://www.unece.org/trans/main/wp29/wp29wgs/wp29grrf/grrf-infmotobrake7.html for a record of all GRRF meetings and 
documents presented therein.
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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

[[Page 54024]]

be similar to existing 49 CFR Part 571 definitions are proposed to be 
added to Sec.  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.
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    \10\ World 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.
    \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.''
    \12\ 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).
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    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.
---------------------------------------------------------------------------

    \13\ See 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.
---------------------------------------------------------------------------

    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 cm\3\ 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 cm\3\ 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 cm\3\ 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 cm\3\ 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 cm\3\ 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 
<plus-minus>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 <plus-
minus> 3.2 km/h (<plus-minus> 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 <plus-minus> 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 <plus-minus> 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

[[Page 54025]]

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 second-last, 
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:

 
------------------------------------------------------------------------
                                   Foot control, FP    Hand control, FL
           Regulation                     (N)                 (N)
------------------------------------------------------------------------
FMVSS No. 122...................  25 < FP < 400.....  10 < FL < 245
UNECE Regulation No. 78/JSS 12-   FP < 350..........  FL < 200
 61.
------------------------------------------------------------------------

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 hand-controlled lever. In an effort 
to define a common practice, the GTR includes a

[[Page 54026]]

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 plug-
type 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 plug-type 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 [deg]C (212 [deg]F), whereas 
FMVSS No. 122 specifies an IBT between 55 [deg]C and 65 [deg]C (130 
[deg]F and 150 [deg]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 [deg]C and 100 [deg]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 fps\2\ with an IBT between 55 
[deg]C and 65 [deg]C (130 [deg]F and 150 [deg]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 round-off 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 [deg]C to 65 
[deg]C currently specified in FMVSS No. 122 to an IBT less than or 
equal to 100 [deg]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.

[[Page 54027]]

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.
---------------------------------------------------------------------------

    \14\ As 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).
---------------------------------------------------------------------------

    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.
---------------------------------------------------------------------------

    \15\ These studies will be posted in the current docket.
---------------------------------------------------------------------------

    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/s\2\ 
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

[[Page 54028]]

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 high-speed 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/s\2\ 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/s\2\. 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/s\2\ from 100 mph, compared to 
the JSS 12-61 MFDD of 5.8 m/s\2\ 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.
---------------------------------------------------------------------------

    \16\ This study will be posted in the current docket.
---------------------------------------------------------------------------

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

[[Page 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 [deg]C 
and 100 [deg]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/s\2\ 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

[[Page 54030]]

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 lightly-loaded 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 high-friction 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 low-friction surfaces, a high-friction 
surface to low-friction surface transition stop and a low-friction 
surface to high-friction 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:
    <bullet> 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.
    <bullet> 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.
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    \17\ ABS performance test reviews used in the drafting of GTR 
provisions will be posted in the docket.
---------------------------------------------------------------------------

    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

[[Page 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:
    <bullet> Rider safety. The test requires that the rider achieve an 
impending locked-wheel 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-of-control 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.
    <bullet> 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 low-friction 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 
low-friction 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.

[[Page 54032]]

    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

[[Page 54033]]

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 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 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:
    <bullet> 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.
    <bullet> 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.
    <bullet> We propose that the initial brake temperature (IBT) be 
measured by plug-type 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.
    <bullet> 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.''
    <bullet> 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.

[[Page 54034]]

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).
    <bullet> 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 Sec.  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

[[Page 54035]]

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

[[Page 54036]]

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:
    <bullet> Have we organized the material to suit the public's needs?
    <bullet> Are the requirements in the rule clearly stated?
    <bullet> Does the rule contain technical language or jargon that 
isn't clear?
    <bullet> Would a different format (grouping and order of sections, 
use of headings, paragraphing) make the rule easier to understand?
    <bullet> Would more (but shorter) sections be better?
    <bullet> Could we improve clarity by adding tables, lists, or 
diagrams?
    <bullet> 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

[[Page 54037]]

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:


Sec.  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 two-wheeled motorcycle with an 
engine cylinder capacity in the case of a thermic engine not exceeding 
50 cm\3\ 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 cm\3\ and whatever the means of 
propulsion a maximum design speed not exceeding 50 km/h.
    Category 3-3 motorcycle means a two-wheeled motorcycle with an 
engine cylinder capacity in the case of a thermic engine exceeding 50 
cm\3\ 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 cm\3\ 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 cm\3\ 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

[[Page 54038]]

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[middot]V + 
(X)[middot]V<SUP>2</SUP>,

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[middot]Vs + 
(Sa - 0.1[middot]Va)[middot]Vs<SUP>2</SUP>/Va<SUP>2</SUP>,

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



[[Page 54039]]


    Note to S5.3.1(b): This equation is only valid when the actual 
test speed (Va) is within <plus-minus> 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 high-
friction surface has a peak braking coefficient (PBC) of 0.9.
    S6.1.1.2 Low-friction surface. A low-friction 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 two-wheeled 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 
[deg]C and 45 [deg]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 <plus-
minus> 5 km/h. In the event of the actual test speed deviating from the 
specified test speed (but within the <plus-minus> 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 [deg]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/s<SUP>2</SUP> for motorcycle categories 3-3 and 3-5
    (ii) 1.5-2.0 m/s<SUP>2</SUP> for motorcycle categories 3-1 and 3-2
    (2) Single rear brake system only: 1.5-2.0 m/s<SUP>2</SUP>
    (3) CBS or split service brake system: 3.5-4.0 m/s<SUP>2</SUP>
    (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 
[deg]C and <= 100 [deg]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.

[[Page 54040]]

    (b) Lightly loaded.
    (c) Engine disconnected.
    S6.4.2 Test conditions and procedure.
    (a) Initial brake temperature. Initial brake temperature is >= 55 
[deg]C and <= 100 [deg]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 V\2\ (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 
[deg]C and >= 100 [deg]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 V\2\ (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[deg] 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[deg] 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[deg] 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/s\2\, 
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

[[Page 54041]]

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 
[deg]C and <= 100 [deg]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[deg] C and <= 100 [deg]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/s\2\ 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 S<INF>2</INF> shall be <= 1.67 S<INF>1</INF>- 0.67 x 0.1V,

Where:
S<INF>1</INF> = corrected stopping distance in meters achieved in 
the baseline test set out in S6.7.2.
S<INF>2</INF> = 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 
[deg]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 anti-lock 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 
[deg]C and <= 100 [deg]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.

[[Page 54042]]

    (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 
[deg]C and <= 100 [deg]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 
[deg]C and <= 100 [deg]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 
[deg]C and <= 100 [deg]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.

[[Page 54043]]

    (a) Initial brake temperature. Initial brake temperature is >= 55 
[deg]C and <= 100 [deg]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 V\2\ 
(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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    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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