NOTEWORTHY PRACTICES 1

MOTORCYCLE SAFETY NOTEWORTHY PRACTICES: 

Infrastructure and 

Engineering

FHWA-SA-22-032
Notice

This document is disseminated under the sponsorship of the U.S. Department 

of Transportation in the interest of information exchange. The U.S. Government 

assumes no liability for the use of the information contained in this document.

The U.S. Government does not endorse products or manufacturers. Trademarks 

or manufacturers’ names appear in this report only because they are considered 

essential to the objective of the document.

Quality Assurance Statement 

The Federal Highway Administration (FHWA) provides high-quality information 

to serve Government, industry, and the public in a manner that promotes public 

understanding. Standards and policies are used to ensure and maximize the 

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improvement. 

Cover Photo Source: Texas A&M Transportation Institute (TTI)
TECHNICAL REPORT DOCUMENTATION PAGE 

1. Report No.

FHWA-SA-22-031

2. Government Accession No. 3. Recipient’s Catalog No.

4. Title and Subtitle

Motorcycle Safety Noteworthy Practices: Infrastructure 

and Engineering

5. Report Date

June 2022

6. Performing Organization 

Code

7. Authors

Georgene Geary and Michael Manser

8. Performing Organization 

Report No.

9. Performing Organization Name and Address

Texas A&M Transportation Institute

The Texas A&M University System

College Station, Texas 77843-3135

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

693JJ320D000023

12. Sponsoring Agency Name and Address

U.S. Department of Transportation

Federal Highway Administration

1200 New Jersey Avenue, SE

Washington, DC 20590

13. Type of Report and Period 

Covered

Final Report

14. Sponsoring Agency Code

15. Supplementary Notes

Task Order Manager for this report is Guan Xu.

Project Title: Addressing the Motorcyclist Advisory Council Recommendations

16. Abstract

Motorcyclists are at significantly greater risk of fatalities and injuries when involved in a 

crash compared to passenger vehicle drivers. A general source of this risk is associated 

with the roadway infrastructure and can include items like reduced friction surfaces, poor 

roadway maintenance, and barriers. While research has examined a variety of roadway 

infrastructure countermeasures to improve motorcyclist safety in terms of reducing the 

propensity for a crash and reducing the severity of a crash after one occurs, there is 

a need to transfer this information to practitioners so that the countermeasures can 

be implemented. This report contains summary information on nine infrastructurebased countermeasures intended to improve motorcyclist safety. The countermeasures 

are presented as noteworthy practices that are in use currently by one or more State 

departments of transportation. 

17. Key Words

Motorcycle safety, noteworthy practices, advisory sign, 

steel plates, high-friction surface treatment, road safety 

audit, work zone, friction and pavement markings, 

protection system, barriers

18. Distribution Statement

No restrictions. This document 

is available to the public 

through the National Technical 

Information Service Alexandria, 

Virginia 22312

19. Security Classif. 

(of this report)

Unclassified

20. Security Classif. (of this 

page)

Unclassified

21. No of Pages

32

22. Price

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized
SI* (Modern Metric) Conversion Factors

APPROXIMATE CONVERSIONS TO SI UNITS

Symbol When You Know Multiply By To Find Symbol

Length

in inches 25.4 millimeters mm

ft feet 0.305 meters m

yd yards 0.914 meters m

mi miles 1.61 kilometers km

Area

in2 square inches 645.2 square millimeters mm2

ft2 square feet 0.093 square meters m2

yd2 square yard 0.836 square meters m2

ac acres 0.405 hectares ha

mi2 square miles 2.59 square kilometers km2

Volume

fl oz fluid ounces 29.57 milliliters mL

gal gallons 3.785 liters L

ft3 cubic feet 0.028 cubic meters m3

yd3 cubic yards 0.765 cubic meters m3

NOTE: volumes greater than 1000 L shall be shown in m3

Mass

oz ounces 28.35 grams g

lb pounds 0.454 kilograms kg

T short tons (2000 lb) 0.907 megagrams (or “metric ton”) Mg (or “t”)

Temperature (exact degrees)

°F Fahrenheit 5 (F-32)/9 

or (F-32)/1.8 Celsius °C

Illumination

fc foot-candles 10.76 lux lx

fl foot-Lamberts 3.426 candela/m2 cd/m2

Force and Pressure or Stress

lbf poundforce 4.45 newtons N

lbf/in2 poundforce per square inch 6.89 kilopascals kPa

APPROXIMATE CONVERSIONS FROM SI UNITS

Symbol When You Know Multiply By To Find Symbol

Length

mm millimeters 0.039 inches in

m meters 3.28 feet ft

m meters 1.09 yards yd

km kilometers 0.621 miles mi

Area

mm2 square millimeters 0.0016 square inches in2

m2 square meters 10.764 square feet ft2

m2 square meters 1.195 square yards yd2

ha hectares 2.47 acres ac

km2 square kilometers 0.386 square miles mi3

Volume

mL milliliters 0.034 fluid ounces fl oz

L liters 0.264 gallons gal

m3 cubic meters 35.314 cubic feet ft3

m3 cubic meters 1.307 cubic yards yd3

Mass

g grams 0.035 ounces oz

kg kilograms 2.202 pounds lb

Mg (or “t”) megagrams (or “metric ton”) 1.103 short tons (2000 lb) T

Temperature (exact degrees)

°C Celsius 1.8C+32 Fahrenheit °F

Illumination

lx lux 0.0929 foot-candles fc

cd/m2 candela/m2 0.2919 foot-Lamberts fl

Force and Pressure or Stress

N newtons 0.225 poundforce lbf

kPa kilopascals 0.145 poundforce per square inch lbf/in2

*SI is the symbol for the International System of Units. Appropriate rounding should be made to comply with 

Section 4 of ASTM E380. (Revised March 2003)
INTRODUCTION

On December 25, 2015, President Obama signed the Fixing 

America’s Surface Transportation (FAST) Act. This legislation 

reestablished the Motorcyclist Advisory Council (MAC) and 

authorized MAC to address “infrastructure issues of concern to 

motorcyclists.” The MAC recommendations specifically addressed 

“road design, construction, and maintenance practices” and their 

influence on motorcycle safety.* MAC identified the following 11 

areas related to infrastructure maintenance and construction that 

affect motorcyclists’ safety: 

• Pothole maintenance.

• Open milled road surfaces.

• Raised manhole covers.

• Steel plates.

• Uneven pavement conditions.

• Gravel or debris on roadway.

• Traffic barrel sight criteria.

• Chip seals.

• Excessive over-band crack fillers and joint sealant.

• Low-friction pavement markings.

• Traffic-actuated signal detection systems that do not detect a 

motorcycle.

* The full MAC report and other safety resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
Source: TTI
CONTENTS

This document is a compilation of noteworthy practices (NPs) that address one 

or more of the MAC-identified areas of infrastructure concern. The NPs included 

herein are:

Work Zone Safety Training Specifically Related to Motorcycles .................. 8

Temporary Steel Plates.............................................................................. 10

Friction and Pavement Markings, Southern States*................................... 12

Friction and Pavement Markings, Northern States*................................... 14

Motorcycle Advisory Sign Guidance.......................................................... 16

Detecting Motorcycles at Traffic Signals .................................................... 18

High-Friction Surface Treatment for Motorcycle Safety in Curves ............. 20

Motorcycle Road Safety Audit.................................................................... 22

Motorcycle Protection System ................................................................... 24
 8 NOTEWORTHY PRACTICES

NOTEWORTHY PRACTICE—

WORK ZONE SAFETY TRAINING SPECIFICALLY 

RELATED TO MOTORCYCLES

Source: National Workzone Safety Information Clearinghouse website, https://www.workzonesafety.org

NATIONAL WORK ZONE SAFETY 

INFORMATION CLEARINGHOUSE 

(WORKZONESAFETY.ORG)

Subject Areas*: Pothole Maintenance, Open 

Milled Road Surfaces, Raised Manhole Covers, 

Steel Plates, Uneven Pavement Conditions, 

Gravel or Debris on Roadway, Traffic Barrel Sight 

Criteria, Chip Seals, Excessive Over-Band Crack 

Fillers, Low-Friction Pavement Markings, TrafficActuated Signal Detection Systems

Strategy

• Access clearinghouse and training resource 

to address motorcycle safety

BACKGROUND 

Motorcycles comprise only 3 percent of the registered vehicles 

and only 0.6 percent of vehicle miles traveled but account for 

14 percent of motor vehicle traffic fatalities.(1) This means that 

motorcycles are overrepresented in fatal accidents in the United 

States. Awareness of the special needs of motorcyclists could go 

a long way in combating these grim statistics.

CHALLENGES

A recent research synthesis on motorcycle safety(1) found that very 

few State construction specifications even consider the special 

needs of motorcycles. The report also noted a lack of training 

for engineers, contractors, and agency personnel concerning 

the specific aspects of motorcycle safety. On a positive note, 

one training source that was identified does have the opportunity 

to have a huge impact on motorcycle safety. The National 

Work Zone Safety Information Clearinghouse (workzonesafety.

org) is a highly successful public-private partnership focused 

* The Motorcyclist Advisory Council (MAC) identified 11 areas related to infrastructure that affect motorcyclists’ safety. The full MAC report and 

other resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
NOTEWORTHY PRACTICES 9

on work zone safety. The site, funded by a Federal Highway 

Administration (FHWA) grant, was initiated in 1997. The website 

and the American Road and Transportation Builders Association 

(ARTBA) Work Zone Safety Online Management System are 

managed by the ARTBA Transportation Development Foundation 

(TDF). The website resources have been used by all 50 States, 

Puerto Rico, and other countries. 

NOTEWORTHY PRACTICE DESCRIPTION

Recent efforts sponsored by FHWA and the Texas Department 

of Transportation (TxDOT) have provided new training materials 

specifically focused on motorcycle safety. TxDOT, through the 

Texas Transportation Institute, developed a 30-minute online 

training module named “Reducing Risks to Motorcycles in Texas 

Work Zones.” While this training is specific to Texas, ARTBA TDF 

has also developed a one-hour online training program, “Work 

Zone Safety for Motorcycles and Bicycles,” which covers work 

zones in general and even includes a quiz and certificate of 

completion.(2) The website also provides a guide that specifically 

addresses motorcyclist and bicyclist safety needs around work 

zones titled Guidelines on Motorcycle and Bicycle Work Zone 

Safety.(3) The guide (see Figure 1) includes eight recommended 

practices and actions agencies can take to address motorcycle 

safety in the areas of: 

• Addressing pavement unevenness.

• Using appropriate design speeds in work zones.

• Using advanced warning signs specifically for 

motorcycles.

• Using portable (changeable) message signs as needed 

for added visibility.

• Addressing steel plates.

• Being cognizant of pavement markings’ effect on 

motorcycles.

• Including motorcycles in agency guidelines and design 

policy.

• Regularly monitoring pavement conditions.

TAKEAWAYS/LESSONS LEARNED

The next step is to share the training and make others aware of 

the benefits of this training. This course offers training on how to 

design and operate work zones with motorcyclists’ safety in mind: 

https://artba.ispringmarket.com/content/81/info/Work_Zone_

Safety_for_Motorcycles_and_Bicycles_-_BETA_Version

Figure 1. Cover of 

ARTBA guidelines.

Source: ARTBA website, 

https://workzonesafetymedia.s3.amazonaws.

com/workzonesafety/

files/documents/training/

courses_programs/

rsa_program/RSP_

Guidance_Documents_

Download/RSP_

MotorcyclesGuidance_

Download.pdf

REFERENCES

1. Geary, G., Dixon, K., Aspelin, K., & Manser, M. 

(2021). Addressing the Motorcyclist Advisory Council 

recommendations: Synthesis on roadway geometry, 

pavement design, and pavement construction 

and maintenance practices (Report No. FHWASA-21-090). Federal Highway Administration. https://

safety.fhwa.dot.gov/motorcycles/docs/FHWASA-21-090_Addressing_MAC_Recommendations_

Rpt.pdf

2. American Road and Transportation Builders 

Association. (n.d.). Workzone safety for motorcycles 

and bicycles. https://artba.ispringmarket.com/

content/81/info/Work_Zone_Safety_for_Motorcycles_

and_Bicycles_-_BETA_Version 

3. American Road and Transportation Builders 

Association. (2011). Guidelines on Motorcycle and 

Bicycle Workzone Safety. https://www.workzonesafety.

org/files/documents/training/courses_programs/

rsa_program/RSP_Guidance_Documents_Download/

RSP_MotorcyclesGuidance_Download-508.pdf
 10 NOTEWORTHY PRACTICES

TEMPORARY STEEL PLATES

NOTEWORTHY PRACTICE—

Source: Shutterstock

CITY OF ATLANTA DOT

Subject Area*: Steel Plates 

Strategies

• Develop detailed standard for temporary 

steel plates

• Identify advanced signage

• Identify tape markings for visibility

• Identify standard taper details

BACKGROUND

Roadways not only move vehicular traffic, sometimes they also 

include underground utilities that travel across or even along a 

roadway. Maintenance crews typically access these underground 

utilities by trenching the roadway. Steel plates are often used to 

cover the open trenches to allow traffic to continue to use the 

roadway while work is being performed on the underground 

facilities. While all vehicles can experience adverse impacts from 

improperly installed steel plates, motorcyclists find the plates 

especially challenging. The Motorcyclist Advisory Council (MAC) 

identified steel plates as one of the 11 specific construction and 

maintenance practices of concern. MAC noted that steel plates 

often are raised, creating a jarring bump and providing limited 

friction.

CHALLENGES 

Steel plates are typically greater than an inch in thickness, which 

can jar a motorcyclist if not recessed or tapered in correctly. 

The surface of the steel plate, if untreated, can become slick 

during a rain event or when covered with leaves. It has been 

documented that some State Departments of Transportation 

(DOTs), like Delaware DOT, have standard details for tapering 

in the steel plates. In addition, Washington State DOT requires 

advanced warning signs for steel plates. Virginia DOT performed 

research on steel plates and recommended reflective tape be 

used on the corners of the plates to assist motorcyclists in being 

more aware of the plates.(1) All of these methods are beneficial 

to motorcyclists because they provide awareness, reduce the 

pavement unevenness, and improve frictional properties—all 

factors that influence motorcyclists’ safety.

 * The Motorcyclist Advisory Council (MAC) identified 11 areas related to infrastructure that affect motorcyclists’ safety. The full MAC report and other 

resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
NOTEWORTHY PRACTICES 11

NOTEWORTHY PRACTICE DESCRIPTION

The City of Atlanta Public Right-of-Way Manual(2) includes specific 

requirements for steel plates used for temporary purposes that 

includes all the recommended practices in one manual. The 

document specifically notes the following: 

• “Metal plates shall be coated with a skid-resistant 

finish.”

• “Metal plates will have white reflective marking tape on 

all four corners of each end plate” (see Figure 2).

The manual also includes details for recessing steel plates on 

high-speed roadways to provide for a smoother surface (Figure 3).

TAKEAWAYS/LESSONS LEARNED

Roadway cuts are especially common in utility-heavy metropolitan 

areas. Metal plates are often used as temporary measures to 

keep the roadway open to traffic as the underground work is 

progressing. Clear and concise guidance on how to reduce 

the risk from metal plates to motorcyclists and other road users 

(bicyclists would also benefit, especially in metropolitan areas) 

should be shared and emulated.

REFERENCES

1. Geary, G., Dixon, K., Aspelin, K., & Manser, M. 

(2021). Addressing the Motorcyclist Advisory Council 

recommendations: Synthesis on roadway geometry, 

pavement design, and pavement construction 

and maintenance practices (Report No. FHWASA-21-090). Federal Highway Administration. https://

safety.fhwa.dot.gov/motorcycles/docs/FHWASA-21-090_Addressing_MAC_Recommendations_

Rpt.pdf

2. City of Atlanta Department of Public Works, Office 

of Transportation. (2019). City of Atlanta public rightof-way manual. https://www.atlantaga.gov/home/

showpublisheddocument?id=44400

Figure 2. White 

reflective marking tape 

on metal plates.

Source: City of Atlanta 

Public Right-of-Way 

Manual

Figure 3. Recessing steel plates 

on higher-speed roadways.

Source: City of Atlanta Public 

Right-of-Way Manual
 12 NOTEWORTHY PRACTICES

NOTEWORTHY PRACTICE—

FRICTION AND PAVEMENT MARKINGS, SOUTHERN STATES*

Source: Shutterstock

FLORIDA DOT

Subject Area**: Low-Friction Pavement 

Markings

Strategies

• Specify frictional properties for pavement 

markings that cover large areas

• Consider installing demo projects through 

maintenance

BACKGROUND

Friction on the roadway is especially important for motorcycles 

due to the lower number of contact points (two tires versus 

four) and importance of each of these contact points in overall 

stability. While pavement friction itself is often measured, friction 

of the pavement markings that go on top of the pavement is not 

always measured. States are increasing the use of pavement 

markings placed in the center of a lane to assist motorists, like 

interstate shields used for guidance (Figure 4). The Manual 

on Uniform Traffic Control Devices (MUTCD) Section 3B.20 

describes pavement word, symbol, and arrow markings in use, 

including these interstate shields. The MUTCD does note that 

“consideration should be given to selecting pavement marking 

materials that will minimize tripping or loss of traction for road 

users, including pedestrians, bicyclists, and motorcyclists.”(1)

However, research has shown that it can be difficult to provide 

for both retroreflectivity and friction of pavement markings at 

the same time.(2) Therefore, some of these large markings, due 

to their large surface area and need for retroreflectivity, can 

potentially provide a loss of friction in wet or damp conditions, 

particularly for motorcyclists. 

CHALLENGES 

Daytona Beach, Florida, is a well-known destination for many 

tourists. During the annual Bike Week event, the area particularly 

attracts motorcycists. I-95 is the main interstate route north and 

south of Daytona Beach. Florida DOT is adding shields to some 

high-profile roadways to improve guidance and potentially reduce 

wrong-way crashes. The DOT recently added shield markings on 

I-95 near Daytona Beach. As shown in Figure 5, the shields cover 

a large portion of the lane, limiting the ability to traverse the lane 

without crossing over the pavement marking. Frictional properties 

of pavement markings are a noted concern of motorcyclists.(2)

 * Pavement markings tend to be different in northern and southern States due to climate.

 ** The Motorcyclist Advisory Council (MAC) identified 11 areas related to infrastructure that affect motorcyclists’ safety. The full MAC report and other 

resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
NOTEWORTHY PRACTICES 13

NOTEWORTHY PRACTICE DESCRIPTION 

Due to the potential volume of motorcycles on the road, Florida 

DOT specified pavement marking materials for an I-95 pavement 

marking maintenance project that would provide additional 

frictional characteristics for the shields and words placed on the 

pavement. Florida DOT District 5 engineers worked with local 

suppliers to make sure they could meet the higher frictional 

requirements. The project was a success, and the use of these 

high-type pavement materials will be considered in the future. 

TAKEAWAYS/LESSONS LEARNED

Florida DOT has been a champion of motorcyclists’ safety 

for many years; it was recognized with a National Roadway 

Safety Award in 2011 by FHWA for making roadways safer for 

motorcycles.(3)

Florida DOT already has requirements in its specifications for 

pavement markings with frictional properties.(4) These markings 

are used in crosswalks and bicycle facilities. Florida DOT 

specifications allow a slightly lower initial retroreflectivity (275 

instead of 300 mcd/lx*m2) for these high-friction markings 

since the DOT recognizes the trade-off between friction and 

retroreflectivity is currently necessary. The project was a success, 

and the use of these high-type pavement materials are now being 

considered as a standard for the future.

REFERENCES

1. Federal Highway Administration. (2012). Manual 

on uniform traffic control devices for streets and 

highways. FHWA.

2. Geary, G., Dixon, K., Aspelin, K., & Manser, M. 

(2021). Addressing the Motorcyclist Advisory Council 

recommendations: Synthesis on roadway geometry, 

pavement design, and pavement construction 

and maintenance practices (Report No. FHWASA-21-090). Federal Highway Administration. https://

safety.fhwa.dot.gov/motorcycles/docs/FHWASA-21-090_Addressing_MAC_Recommendations_

Rpt.pdf

3. Federal Highway Administration. (2011). National 

Roadway Safety Awards: Noteworthy practices guide. 

https://rspcb.safety.fhwa.dot.gov/noteworthy/html/

vulnerableroadusers_fl.aspx?id=104

4. Florida DOT. (2022). Standard specifications for 

road and bridge construction. https://fdotwww.

blob.core.windows.net/sitefinity/docs/defaultsource/programmanagement/implemented/

specbooks/january-2022/january2022-ebook.

pdf?sfvrsn=752d1333_4

Figure 4. MUTCD 

Fig. 3B-25.

Source: Manual 

on Uniform Traffic 

Control Devices

Figure 5. I-95 near 

Daytona beach.

Source: Florida 

DOT
 14 NOTEWORTHY PRACTICES

NOTEWORTHY PRACTICE—

FRICTION AND PAVEMENT MARKINGS, NORTHERN STATES*

Source: Shutterstock

MINNESOTA DOT

Subject Area**: Low-Friction Pavement 

Markings

Strategies

• Consider friction management for 

pavement markings 

• Identify locations in need of enhanced friction

BACKGROUND

Friction on the roadway is especially important for motorcycles 

due to the lower number of contact points (two tires versus 

four) and importance of each of these contact points in overall 

motorcycle stability. While pavement friction itself is often 

measured, friction of the pavement markings that typically go on 

top of the pavement is not always measured.

The Manual on Uniform Traffic Control Devices notes that 

“consideration should be given to selecting pavement marking 

materials that will minimize tripping or loss of traction for road 

users, including pedestrians, bicyclists, and motorcyclists.”(1)

However, research has noted that it can be difficult to provide 

for both retroreflectivity and friction of pavement markings at 

the same time.(2) In addition, in northern States, snowplows 

can cause early failure of pavement markings. To address this 

situation, Minnesota DOT commonly recesses its longitudinal 

pavement markings and pavement messages to reduce damage 

by snowplows; however, placing recessed markings within 

the lane in a curve, like those needed for roundabouts, can be 

problematic. 

CHALLENGES

Minnesota DOT is increasingly utilizing roundabouts as a proven 

safety countermeasure since roundabouts have been shown 

to provide about an 80 percent reduction in severe crashes 

compared to typical intersections.(2) In fact, Minnesota is one 

of the top 10 States in roundabout use. Pavement markings 

are often used to assist in guidance through roundabouts, but 

recessed pavement markings are not the whole solution since 

the markings are large and placed within the driving portion of the 

lane (see Figure 6).

* Pavement markings tend to be different in northern and southern States due to climate.

** The Motorcyclist Advisory Council (MAC) identified 11 areas related to infrastructure that affect motorcyclists’ safety. The full MAC report and other 

resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
NOTEWORTHY PRACTICES 15

NOTEWORTHY PRACTICE DESCRIPTION

Due to motorcycle community concerns with the pavement 

markings used in roundabouts, Minnesota DOT is testing a new 

method using methyl-methacrylate-enhanced skid-resistance 

markings that include an application of skid-resistant aggregate. 

Figure 6 shows the roundabout with the new markings located on 

SR 22 in Mankato, southwest of Minneapolis. A recent research 

report published by FHWA(3) identified the need for friction of 

pavement markings but found limited research in the United 

States. The FHWA work did identify some research in progress 

in Minnesota.

Minnesota DOT has a first-of-its-kind (in over 40 years) 

research project underway at the University of Minnesota that 

is investigating differential friction effects caused by pavement 

markings; the project is titled Pavement Marking/Colored 

Pavement Friction Differential and Product Durability.(4) The 

Minnesota DOT research project will test existing and newly 

developed pavement marking materials in a variety of ways and 

conditions. The research will also test the surrounding pavement 

to identify potential problems arising from friction differentials. 

Figure 6. Roundabout markings.

Source: Minnesota DOT

Minnesota DOT also commonly uses motorcycle-friendly 

pedestrian crosswalks (shown in Figure 7) that leave openings in 

the wheelpaths for motorcycles. 

In addition, Minnesota DOT has a technical memorandum 

on pavement marking operations(5) that includes a section 

specifically related to skid resistance. As part of this document, 

the DOT also identifies locations where enhanced friction 

materials should be used, such as crosswalks, railroad crossings, 

stop lines, and “stop ahead” pavement markings. The Minnesota 

DOT specifications include enhanced skid-resistant marking 

requirements that require a British pendulum number of > 60 for 

pavement markings. 

TAKEAWAYS/LESSONS LEARNED

As shown in its crosswalk detail and technical memorandum, and 

in its pursuit of friction research, Minnesota DOT recognizes the 

importance of pavement marking friction. The roundabout special 

project is just another way Minnesota DOT is trying to improve the 

safety of the travel experience for motorcyclists and all roadway 

users.

REFERENCES

1. Federal Highway Administration. (2012). Manual 

on uniform traffic control devices for streets and 

highways. FHWA.

2. Geary, G., Dixon, K., Aspelin, K., & Manser, M. 

(2021). Addressing the Motorcyclist Advisory Council 

recommendations: Synthesis on roadway geometry, 

pavement design, and pavement construction 

and maintenance practices (Report No. FHWASA-21-090). Federal Highway Administration. https://

safety.fhwa.dot.gov/motorcycles/docs/FHWASA-21-090_Addressing_MAC_Recommendations_

Rpt.pdf

3. Federal Highway Administration. (2021). 

Roundabouts. https://safety.fhwa.dot.gov/

provencountermeasures/roundabouts.cfm

4. Minnesota Department of Transportation. (2021). 

New project: Pavement marking/colored pavement 

friction differential and product durability. https://

mntransportationresearch.org/2021/09/10/newproject-pavement-marking-colored-pavement-frictiondifferential-and-product-durability/

5. Minnesota Department of Transportation. (2019). 

MnDOT provisions for pavement marking operations 

(Technical Memorandum No. 19-05-T-02). https://

edocs-public.dot.state.mn.us/edocs_public/

DMResultSet/download?docId=4899502

Figure 7. Motorcycle-friendly crosswalk markings.

Source: Minnesota DOT
 16 NOTEWORTHY PRACTICES

NOTEWORTHY PRACTICE—

MOTORCYCLE ADVISORY SIGN GUIDANCE

Source: Manual on Uniform Traffic Control Devices

W8

W8-8 W8-9 

W8-15

W8-15P

W8-25W8-24 

Source: GGfGA

MONTANA DOT

Subject Area*: Pothole Maintenance, Open 

Milled Road Surfaces, Uneven Pavement 

Conditions, Gravel or Debris on Roadway

Strategies

• Recognize construction projects that can 

increase the risks to motorcyclists

• Be proactive in making motorcyclists 

aware of construction in time to avoid or 

reroute

• Implement processes to specify, as 

needed, use of signs specifically for 

motorcycles.

BACKGROUND

Pavement rehabilitation projects in Montana often require milling 

the pavement surface or removing the asphalt surface and 

reworking the aggregate base. Traveling through work zones over 

milled or aggregate surfaces can be especially challenging for 

motorcyclists because of induced vehicle instability. In response 

to this concern, several years ago, Montana DOT developed 

specific motorcycle advisory sign guidance.

CHALLENGES

Due to the scenic nature of Montana and the confluence of 

construction and motorcycle riders in the summer, it can be 

expected that motorcycles are on every single road, especially 

during summer construction season. Montana has a 511 website 

(511mt.net) that includes information on construction activities 

(like those shown in Figure 8) on MT200 west of Jordan, but not 

every motorist checks the site before going out on the road. While 

* The Motorcyclist Advisory Council (MAC) identified 11 areas related to infrastructure that affect motorcyclists’ safety. The full MAC report and other 

resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
NOTEWORTHY PRACTICES 17

511mt.net is for all motorists, Montana DOT also has a policy 

specifically related to construction activities and motorcyclists.

NOTEWORTHY PRACTICE DESCRIPTION

Since 2013, Montana has had guidance(1) on advising 

motorcyclists of roadway construction so they can make 

decisions for their traveling comfort and safety. This starts in 

the preconstruction phase of every project (as part of the traffic 

management plan), where the length for the project and any 

associated risks are reviewed for their effect on motorcycles. 

Projects that involve traffic running on temporary gravel roads 

or milled surfaces present potentially adverse conditions for 

motorcycles. These projects are expected to include an advisory 

sign like the one shown in Figure 9. The signs are specific to a 

particular project/route and are strategically placed to allow the 

motorcyclist to stop and check a map or the 511mt.net website 

to identify alternate routes. At the intersection just past the sign 

shown here on Hwy 200, there is a rest area that can be used by 

the motorcyclist.

Figure 8. Montana 511 website showing information on a construction 

project.

Source: Montana DOT 511 website, https://511mt.net

Figure 9. Motorcycle advisory sign on MT Hwy 200.

Source: Jeremy Wilde, Montana DOT

TAKEAWAYS/LESSONS LEARNED

While implementing this new process, Montana DOT interviewed 

a number of motorcyclists to gather their thoughts on the new 

signs versus the “Motorcycle Use Extreme Caution” signs that 

were used previously. The motorcyclists felt that the new signs 

gave much clearer information and provided them with actionable 

options compared to the prior signs. Montana has used this 

signage on a large number of projects, including recent roadwork 

on Hwy 12 east of Helena and Hwy 47 near Hardin. 

Recent research(2) has documented the risks of motorcyclists in 

work zones, and a research project in Ohio(3) has shown that 20 

percent of motorcyclists would travel 20 miles out of the way to 

avoid construction work zones. Since the roads in Montana are 

scenic, that value could be much higher, both in percent and in 

length.

Soliciting feedback from users (motorcyclists) as Montana did 

is also a takeaway. FHWA solicited input from motorcyclists in a 

recent research project looking at different types of novel signage 

specifically for motorcycle safety(4).

REFERENCES

1. Montana Department of Transportation. (2013). 

Motorcycle advisory sign guidance. https://www.

mdt.mt.gov/other/webdata/external/const/wzsm/

motorcycle-advisory-sign-guidance.pdf

2. Geary, G., Dixon, K., Aspelin, K., & Manser, M. 

(2021). Addressing the Motorcyclist Advisory Council 

recommendations: Synthesis on roadway geometry, 

pavement design, and pavement construction 

and maintenance practices (Report No. FHWASA-21-090). Federal Highway Administration. https://

safety.fhwa.dot.gov/motorcycles/docs/FHWASA-21-090_Addressing_MAC_Recommendations_

Rpt.pdf

3. Schneider, W. H., Stakleff, B., & Maistros, A. (2013). 

Examination of factors associated in motorcycle 

crashes in work zones (Report No. FHWA/OH2013/1). Ohio Department of Transportation.

4. Weaver, S.M., Jannat, M., Savolainen, P.T., and 

DeFisher, J. (2021). Novel Highway Signs Study 

to Support Infrastructure-Based Motorcycle Crash 

Countermeasures: Phase II. Report No. FHWAHRT-21-010, FHWA.
 18 NOTEWORTHY PRACTICES

DETECTING MOTORCYCLES AT TRAFFIC SIGNALS

NOTEWORTHY PRACTICE—

Source: Shutterstock

OHIO DOT

Subject Area*: Traffic-Actuated Signal 

Detection Systems

Strategies

• Research the problem and identify 

solutions

• Consider motorcycle detection 

requirement at signalized intersections

BACKGROUND

Due to their smaller size, motorcycles often are not as conspicuous 

as other vehicles on the roadway. This applies to the detection 

of motorcycles at traffic signals as well. Ohio has over 400,000 

registered motorcyclists, the third highest number in the United 

States, behind only California and Florida. Motorcyclists account 

for about 15 percent of the fatal crashes in Ohio but only 3 percent 

of the registered vehicles. A driver colliding with a motorcyclist (or 

other vulnerable user such as a bicyclist or pedestrian) is one of 

the most common intersection crashes in Ohio. Thirty-six percent 

of the motorcycle crashes in Ohio occur at intersections.(1)

CHALLENGES

Dilemma zone detectors (which can be pavement loops or 

pole-mounted radar detectors) detect vehicles approaching an 

intersection and can extend the green light to allow a vehicle to 

safely pass through the intersection on green. If a motorcycle is not 

detected by the dilemma zone detector, the signal could change 

to yellow at a point where it may be necessary for the motorcyclist 

to choose between braking hard or entering the intersection at the 

end of a yellow signal, which could increase the risk of a crash. 

Motorcyclists that are not detected at signalized intersections, 

particularly by dilemma zone detectors, are a safety challenge.

* The Motorcyclist Advisory Council (MAC) identified 11 areas related to infrastructure that affect motorcyclists’ safety. The full MAC report and other 

resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
NOTEWORTHY PRACTICES 19

NOTEWORTHY PRACTICE DESCRIPTION

According to Ohio DOT (personal communication, September 

30, 2021), recognizing the concern of motorcyclists and traffic 

signal detection, engineers at Ohio DOT performed in-house 

research to identify the best methods to detect motorcycles and 

bicycles. Through this research, they found that pavement loop 

detectors that can supply adequate coverage are asymmetrical 

and diagonal to the traffic (Figure 10). They found that some polemounted radar detectors (particularly ones that are larger than 

about 10 inch by 13 inch) can also identify motorcycles better than 

other radar detectors. Pole-mounted detectors have the benefit of 

being able to be installed on bridges and at intersections without 

damage to the bridge or pavement.

Figure 10. Ohio DOT angular design loop detector.

Source: Ohio DOT

The Ohio DOT standard construction specifications (Section 

632.10 Loop Detector Unit) require that “all stop line detection 

zones shall reliably detect motorcycles and bicycles, and all 

dilemma zone detectors shall reliably detect motorcycles.”(2)

In Section 632.28, the standard construction specifications 

include motorcycles in the specific testing requirements for 

pavement loop detectors: “Check the visual call strength indication 

of detector units to determine that each vehicle class (truck, car, 

motorcycle, and bicycle) entering sensor areas is detected on the 

associated detector unit and that no extraneous calls occur when 

the sensor area is vacant.”(2)

The Ohio DOT Traffic Engineering Manual has a special detail 

for the equipment to test loops to make sure they will recognize 

motorcycles.(3) When a stop line detector is not visible, Ohio DOT 

has a special symbol that is placed on the pavement to identify 

where motorcycles and bicycles can be detected (Figure 11). 

Sometimes even correct detectors do not function as expected. 

Ohio DOT maintains a call number and an email address to report 

signal detection issues for motorcycles and bicyclists.

Figure 11. Detector 

marking.

Source: Ohio DOT Traffic 

Engineering Manual

TAKEAWAYS/LESSONS LEARNED

Motorcycles can be detected by using both the common induction 

loops installed in the pavement and pole-mounted radar if the 

detectors are the appropriate configurations, type, and size. Ohio 

DOT has identified detector types that work for both motorcycles 

and bicycles. Its standard specifications and construction details 

clearly show how to install and test the appropriate detection 

systems. Other States could potentially improve their motorcycle 

safety at intersections by implementing signal detection equipment 

that recognizes motorcycles.

REFERENCES

1. Ohio DOT. (2020). Strategic Highway Safety Plan. 

https://www.transportation.ohio.gov/working/

publications/strategic-highway-safety-plan

2. Ohio DOT. (2019). Construction and materials 

specifications. https://www.dot.state.oh.us/Divisions/

ConstructionMgt/OnlineDocs/Pages/2019-OnlineSpec-Book.aspx

3. Ohio DOT. (2022). Traffic engineering manual. https://

www.dot.state.oh.us/roadway/TEM/Pages/default.

aspx
 20 NOTEWORTHY PRACTICES

NOTEWORTHY PRACTICE—

HIGH-FRICTION SURFACE TREATMENT FOR MOTORCYCLE 

SAFETY IN CURVES

Source: Shutterstock

RHODE ISLAND DOT

Subject Area*: High-Friction Surface 

Treatment Strategies

Strategies

• Consider high-friction surface treatment 

installation for curve safety

• Develop motorcycle crash trees to help 

identify risk factors

BACKGROUND

High-friction surface treatment (HFST) is a widely used safety 

countermeasure for run-off-the-road crashes, and it has been 

recognized by the Every Day Counts initiative. FHWA research 

has found that HFST can reduce injury crashes up to 48% at 

horizontal curves.(1) HFST is a thin pavement surfacing composed 

of polish-resistant high-friction aggregate and a polymer binder. 

It is used in spot locations to enhance the friction capability for 

vehicles traversing horizontal curves, intersections, and other 

areas of high-friction demand.

CHALLENGES

Motorcyclists recognize the challenges of driving in wet weather 

and will many times postpone travel, if possible, to prevent 

riding in the rain. However, pavement friction can be reduced in 

a horizontal curve even without wet weather since the highest 

stresses occur in curves; this can result in the surface wearing 

prematurely in a curve, especially curves with small radii. 

Therefore, regardless of weather, crashes in curves can indicate 

a friction problem. 

Also, identifying locations for HFST treatment based on motorcycle 

wet-weather crash rates alone may not be viable due to fewer 

motorcycles on the road than passenger cars and the challenges 

of acquiring accurate motorcycle vehicle miles traveled. 

* The Motorcyclist Advisory Council (MAC) identified 11 areas related to infrastructure that affect motorcyclists’ safety. The full MAC report and other 

resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
NOTEWORTHY PRACTICES 21

NOTEWORTHY PRACTICE DESCRIPTION

Rhode Island installed HFST on a section of Tunk Hill Road in 

Scituate (west of Providence, as shown in Figure 12) based on 

overall crashes in the area. The DOT found that the effort also 

had an influence on motorcycles. There was an average of one 

motorcycle crash per year on this section of road in the five years 

prior to the improvements. After installation of the HFST in 2014, 

there have been no identified motorcycle crashes.

As part of a horizontal curve systemic safety analysis, Rhode 

Island identified “motorcycle related crashes as being an 

overrepresented crash attribute for all fatal and serious injury 

crashes on curves. Almost half occurred within 1,000’ of curves 

with a radius between 50’ and 600’. Additionally, almost half of 

those occurred on curves with an average annual daily traffic 

(AADT) of less than 7,500 vehicles per day. Most motorcycle 

crashes occurred on other principal arterials and minor arterials, 

accounting for 45 (70.3 percent) of KAB motorcycle-involved 

crashes.”(2)

Figure 12. High-friction surface treatment installation

Source: Rhode Island DOT

Based on its safety analysis of crashes from 2014 to 2018, Rhode 

Island developed a crash tree for motorcycle crashes, as shown 

in Figure 13. The DOT also identified a potential relationship 

between curve radius and KAB motorcycle curve crashes(3):

Predicted KAB curve crashes as a function of radius = 11.895 * 

Radius−0.288.

This relationship is being considered, along with functional 

class and AADT, to perform risk scoring related to motorcycleinvolved crash locations. Based on the Tunk Hill Road and other 

HFST project results, Rhode Island is now considering HFST 

as a potential countermeasure for motorcycle crashes in curved 

sections.

TAKEAWAYS/LESSONS LEARNED

HFST may also benefit motorcyclists, who do not travel as much 

in inclement weather, and so do not show up as a factor in wetweather crashes.(3) Curves that experience motorcycle crashes 

should be considered for HFST, not just total wet-weather 

crashes. 

Figure 13. Motorcycle crash decision 

tree.

Source: Rhode Island DOT

REFERENCES

1. Federal Highway Administration. (2022). Safety: 

Proven Safety Countermeasures: Pavement 

Friction Management. https://safety.fhwa.dot.gov/

provencountermeasures/pavement-friction.cfm

2. VHB. (2021). Rhode Island DOT horizontal curve 

systemic safety analysis summary draft document 

(unpublished).

3. Geary, G., Dixon, K., Aspelin, K., & Manser, M. 

(2021). Addressing the Motorcyclist Advisory Council 

recommendations: Synthesis on roadway geometry, 

pavement design, and pavement construction 

and maintenance practices (Report No. FHWASA-21-090). Federal Highway Administration. https://

safety.fhwa.dot.gov/motorcycles/docs/FHWASA-21-090_Addressing_MAC_Recommendations_

Rpt.pdf

Source: TTI
 22 NOTEWORTHY PRACTICES

NOTEWORTHY PRACTICE—

MOTORCYCLE ROAD SAFETY AUDIT

Source: Shutterstock

TENNESSEE DOT

Subject Area*: Barrier Design and Other 

Special Motorcyclists Needs

Strategies

• Conduct road safety audit for motorcycle 

safety

• Recognize the special needs of 

motorcyclists

BACKGROUND

Roads are primarily seen as a method to get from point A to point 

B, and the most direct connection between two points is a straight 

line. Mountainous roads typically contain a lot of curves to allow 

for increasing elevation without being too steep. 

Over time, some roads have become not just a part of the 

destination from A to B, but the destination itself. US 129/SR 115 

is one of those roads (see Figure 14). Known in motorcycle circles 

as the “Tail of the Dragon,” it is a mountainous road located in 

the northeast side of Tennessee, south of Knoxville. It is heavily 

traveled by motorcyclists, and it is so famous that each of the 318 

curves on the 11 mile road has its own name.(1)

CHALLENGES

Tight curves, speed, and motorcycles are a precarious 

combination. A recent synthesis for FHWA on motorcycle safety 

noted that the lengths and radii of horizontal curves are two 

features that significantly influence motorcycle crash frequency. 

The report identified one study that found horizontal curves with 

radii less than 500 ft were 40 times more likely to have motorcycleto-barrier crashes than curves with radii of 2,800 ft or greater.

(2) The study also found horizontal curves with radii of 820 ft or 

less can be expected to increase crash frequency by a factor of 

10. Another study discussed in the same synthesis report found 

that reverse curves were associated with an increase of about 6 

percent in fatal or serious injury crashes.(2) US 129/SR 115 has 

both tight curves and reverse curves.

* The Motorcyclist Advisory Council (MAC) identified 11 areas related to infrastructure that affect motorcyclists’ safety. The full MAC report and other 

resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
NOTEWORTHY PRACTICES 23

Figure 14. Tennessee US 129/ SR 115.

Source: Google Earth

NOTEWORTHY PRACTICE DESCRIPTION

Recognizing the realities of the Tail of the Dragon, Tennessee 

DOT has performed road safety audits (RSA) and operational 

improvement studies on this section of roadway (Tennessee 

DOT, personal communication, September 30, 2021). Along 

with the typical engineering and law enforcement members, 

Tennessee DOT also invited motorcycle club members to be a 

part of the RSA. Surprising to the other attendees, the motorcycle 

club members identified guardrails as one of the main concerns. 

As part of the RSA and an operations safety review, Tennessee 

DOT looked specifically at the guardrail locations to determine if 

they could be graded such that it could remove the guardrail. The 

DOT identified pull-off locations that could be paved to allow a 

motorcyclist to pull over safely. Also, a major change that resulted 

from the review was the removal of slower-moving trucks from 

this section of road. Trucks over 30 ft in length were rerouted from 

this section of US 129. Long trucks and tight curves can make the 

road impassible at times, potentially creating a safety concern. 

More recently, another review resulted in adding half-mile markers 

to the existing mile markers to assist in emergency response. 

Tennessee DOT is also now revisiting this section every year to 

ensure that the roadway itself is not in need of maintenance and 

that the striping and signs are replaced as necessary and are 

clearly visible to the roadway users. 

TAKEAWAYS/LESSONS LEARNED

Road safety audits and operational studies are valuable tools to 

identify potential safety improvements to a section of road. 

Roads can be more than a means to get from point A to point B—

they can also be a destination. When a road has special uses, or 

if previously underserved groups, like motorcyclists, are involved, 

it can be beneficial to get stakeholders involved.

REFERENCES

1. 129 Deals Gap. (n.d.). Tail of the dragon at Deals 

Gap with 318 curves in 11 miles: America’s number 

one motorcycle and sports car road. https://

tailofthedragon.com

2. Geary, G., Dixon, K., Aspelin, K., & Manser, M. 

(2021). Addressing the Motorcyclist Advisory Council 

recommendations: Synthesis on roadway geometry, 

pavement design, and pavement construction 

and maintenance practices (Report No. FHWASA-21-090). Federal Highway Administration. https://

safety.fhwa.dot.gov/motorcycles/docs/FHWASA-21-090_Addressing_MAC_Recommendations_

Rpt.pdf
 24 NOTEWORTHY PRACTICES

MOTORCYCLE PROTECTION SYSTEM

NOTEWORTHY PRACTICE—

Source: TTI

UTAH DOT

Subject Area*: Barrier Design

Strategies

• Identify locations where motorcycles may 

crash into guardrails

• Retrofit guardrails to add motorcycle 

protection systems

BACKGROUND

Motorcyclists are at a much higher risk of injury in crashes 

compared to other motor vehicle occupants. This is especially 

true for run-off-the-road crashes. Traditionally, roadside barriers 

are commonly used to reduce crash severity in these types of 

crashes. However, impacting barriers themselves can be injurious 

or deadly. A recent report noted that motorcyclists account for 

3 percent of registered vehicles but 40 percent of guardrail-impactrelated fatalities.(1) The same report noted that motorcyclists often 

slide into a barrier and end up impacting the support posts instead 

of the intended upper-rail portion of the guardrail.

CHALLENGES

Utah DOT classified locations on State routes where motorcycleguardrail crashes were occurring and identified and installed the 

commercially available motorcycle protection system (MPS) DR46 on State Route 35, which appears to have reduced crashes. 

The commercial product involved sole-source and foreign 

material issues, which made procurement difficult. 

The standard design of a typical guardrail has posts that hold the 

curved rail. The guardrail system is designed to absorb impact 

from a car or truck, so the rail itself is mounted above the ground, 

near the height of a vehicle bumper. While guardrails are designed 

* The Motorcyclist Advisory Council (MAC) identified 11 areas related to infrastructure that affect motorcyclists’ safety. The full MAC report and other 

resources can be found at https://safety.fhwa.dot.gov/motorcycles/.
NOTEWORTHY PRACTICES 25

Figure 15. Utah DOT standard W-beam with powder coating. 

Source: Utah DOT

for typical vehicles, this location of the rail itself also enables the 

posts to be impacted by smaller objects, like motorcyclists that 

have lost control and are sliding along the pavement. MPS add 

a rail element below the standard rail to protect the motorcyclist 

from impacting the posts directly.

NOTEWORTHY PRACTICE DESCRIPTION

While Utah DOT had favorable results with the commercial MPS, 

as noted, procurement was difficult. At the next installation, on 

State Route 191, the DOT performed a retrofit of a standard 

crash-tested guardrail by adding a standard W-beam rail that 

was powder coated yellow. The retrofitted guardrail is shown in 

Figure 15. Prior to installation of the retrofit Utah experienced an 

average of one motorcycle injury crash per year. After installation, 

there were no reported motorcycle crashes in the following three 

years. There has been no indication that the retrofit affected 

crashworthiness of the guardrail. The powder-coated rub rail has 

also maintained the yellow color, even after several winters.

The post transition that was used at the end of the rub rail was 

created by tucking it in behind the rail. The system is only attached 

at every sixth post (about 25 ft) to not create over-stiffening(2) 

(schematics of the system can be found at https://docs.google.

com/presentation/d/1TZjWVrEAgc8VbtKPQvbFvTP3RYKq0rFk

RBPP5-B7hQY/edit#slide=id.g8d21c6e6ab_0_52.

TAKEAWAYS/LESSONS LEARNED

An MPS can be installed on existing guardrails. Sharing 

information on retrofit MPS possibilities may benefit States with 

motorcycle safety guardrail concerns. Utah DOT is also a member 

of the Transportation Pooled Fund TPF-5(482), Development and 

Evaluation of Roadside Safety Systems for Motorcyclists.(3) The 

TPF has an in-service performance evaluation of implemented 

motorcycle safety treatments as one of its specific activities.(3) 

The TPF is also looking at options for other type barriers, like 

the netting shown on the first page for catching motorcyclists that 

may otherwise be ejected over concrete barriers.

REFERENCES 

1. Silvestri-Dobrovolny, C., Geary, G., Dixon, M., Manser, 

M., & Chauhan, J. (2021). Addressing the Motorcyclist 

Advisory Council recommendations: Synthesis on 

barrier design for motorcyclists safety (Report No. 

FHSW-SA-21-069). Federal Highway Administration. 

https://safety.fhwa.dot.gov/motorcycles/docs/FHWASA-21-069_Addressing_MAC_Recommendations_

Rpt.pdf

2. The National Academies. (2020). State panel on 

experience installing motorcycle barrier in the US: 

Utah [Video]. Vimeo. https://vimeo.com/451165246

3. Transportation Pooled Fund. Development 

and evaluation of roadside safety systems for 

motorcyclists. https://www.pooledfund.org/Details/

Study/709
 26 NOTEWORTHY PRACTICES

Source: TTI

MOTORCYCLE SAFETY NOTEWORTHY PRACTICES: 

Infrastructure and 

Engineering

FHWA-SA-22-032

Source: TTI