Design & Equipment
This section contains two categories of research. The first section has research related to the connection between motorcycle design elements and injuries suffered by riders who crash. While a definition of “motorcycle design” might include a wide variety of elements such as wheelbase, fork angle, frame construction, wheel rim construction material and engine configuration, the available research connecting design and injury is mainly focused on fuel tank design – specifically the angle and height of the fuel tank rise. This is a topic not well researched and not often addressed in current motorcyclist safety circles.
The second section is research is related to the connection between crash risk and equipment such as anti-lock braking systems (ABS), traction control, stability control, autonomous emergency braking systems and airbag feasibility studies. Contrary to “design” recent advances in technology have led to “equipment,” especially anti-lock braking and stability control systems, becoming a hot topic with a growing number of research studies.
Design Research Studies
A SMARTER document summarizing this topic.
Abstract. This study aimed to investigate the mechanisms involved in pelvic injuries to crashed motorcyclists. The most frequent cause of pelvic injuries in crashed motorcyclists was due to contact with the motorcycle fuel tank during the crash (85%). The authors conclude improvements in the design of crashworthy motorcycle fuel tanks appear to be required.
2015 – “Can a Boxer Engine Reduce Leg Injuries Among Motorcyclists? Analysis of Injury Distributions in Crashes Involving Different Motorcycles Fitted with Antilock”
The overall motorcycle design can vary across different categories and manufacturers. For instance, some motorcycles are equipped with boxer-twin engines; that is, with protruding cylinder heads. A previous study based on a limited material has suggested that these could provide some leg protection; therefore, the aim of this research was to analyze injury distributions in crashes involving ABS-equipped motorcycles with boxer-twin engines compared to similar ABS-equipped motorcycles with other engine configurations.
Paper presented at the 2014 International Research Council on Biomechanics of Injury conference. This study demonstrates that contact with the motorcycle fuel tank is a major cause of pelvic injury in motorcycle crashes, and these predominantly occur in frontal or oblique collision configurations. It was noted that riders of cruisers were more likely to sustain a pelvic injury than other motorcycle types. This appears to contradict the relationship between the petrol tank angle and level of pelvic loading reported by earlier research as cruisers have a more
2007 – “A Two-rider Motorcycle Accident Involving Injuries Around Groin Area in Both the Driver and the Passenger”
Abstract. This paper presents a two-rider motorcycle accident in which both riders received injuries around the groin area. This study reveals that passengers can also suffer from injuries around the groin area.
This is a presentation paper from the 2006 International Research Council on Biomechanics of Injury conference of the findings of the 2002 research MADYMO Simulation, Reconstruction, and Biomechanical Analysis of Motorcycle Crashes.
This article in Motorcycle Consumer News examines the tank design/groin issue in depth but also goes on to address how gas tank angle contributes to how – or even whether – the rider is ejected from the bike and how ejection is connected to the possibility of rotational brain injury. Moon’s article also addresses how wheel design, stiffness of the front forks, frame construction material and design and handlebar location may contribute to rider injuries in the event of a crash. Available at the msgroup forum at: http://www.msgroup.org/forums/mtt/images/2005-06%20Dangerous%20Design.pdf
The change in trends in motorcycle design means that users of these machines are more prone to pelvic trauma if involved in a direct collision. The high riding fuel tank is in direct contact with the lower abdomen and pelvis when in the normal, prone, riding position. In a direct collision, the fuel tank is driven back into the pelvis. This causes fractures of the pubic rami with extensive soft tissue damage. In general, the accidents that cause these types of injuries are caused by sudden head-on collisions which occur without time to apply the brakes.
This is the title of the original research which was presented as Pelvic Injury Potential and Motorcycle Gas Tanks at the 2006 International Research Council on Biomechanics of Injury conference. Main finding was an exponential increase in both probable pelvic injuries and severity as the height and steepness of the rear of a motorcycle’s gas tank angle in front of the rider increases.
Abstract. Nine patients who sustained severe pelvic lesions as a result of motorcycle accidents were admitted to and treated in the authors' department. The author recommends a national epidemiological study would be useful to evaluate the frequency of such injuries and to draw conclusions leading to improved safety for motorcyclists.
Abstract. The author’s report of patient severe pelvic lesions as a result of motor cycle accidents his call for study to evaluate the frequency of these particular injuries and draw lessons that would lead to better safety of motorcyclists.
1981 – “Motorcycle Accident Cause Factors and Identification of countermeasures Volume I: Technical Report”
The 1981 Hurt Report dedicates eight pages (220-228) to reporting data regarding groin injuries. The authors report “Early in the course of data collection, it became apparent that a substantial number of riders (and some passengers) complained of injury to the groin and often diffuse abdominal pain. In most instances this was associated with a characteristic pattern of damage to the motorcycle in which the top and sides at the back of the fuel tank was deformed inwards.”
This is an abstract of a conference presentation. The authors were part of the “Hurt Study” investigation team and report on the findings. One hundred seventeen of the 900 riders (13%) sustained some type of groin injury, overwhelmingly in frontal collisions involving another vehicle. About 5% of those 117 involved severe injuries such as pubic bone fractures, separation of pubic symphysis, scrotal and bladder lacerations. Motorcycle parts, especially the fuel tank, accounted for about 90% of the injuries. Fuel tank shape affected groin injuries.
This is an International Research Council on Biomechanics of Injury conference paper. The authors report “There were six male occupants who sustained injuries to the perineum, scrotum, testicles or penis. All were operating the motorcycles and were involved in Ejected and Non-ejected collisions. Three were carrying passengers, which may have increased the chance of this type of injury. Three different manufacturers ‘motorcycles were involved. The width and height of the tank relative to the seat affected the injury pattern. Particularly important were the filler cap location and the front fork instrument cluster.”
Equipment Research Studies
The objective of this study was to update the effectiveness estimate for ABS with additional years of data and a broader variety of motorcycle types. Motorcycle drivers involved in fatal crashes per 10,000 registered vehicle years during 2003-19 were examined for 65 motorcycle models offering ABS as an optional feature. Fatal crash rates for motorcycles with ABS were compared with rates for the same models without it. ABS was associated with a statistically significant 22% reduction in motorcycle driver fatal crash involvements per 10,000 registered vehicle years. A good review of this research by Revzilla is here.
2021 – “Motorcycle Autonomous Emergency Braking (MAEB) Employed as Enhanced Braking: Estimating the Potential for Injury Reduction using Real-world Modeling” – ABSTRACT
This study is a follow-up to the field-tests on Motorcycle Autonomous Emergency Braking system (MAEB) which showed that higher levels of deceleration to improve its effectiveness were feasible. However, the potential of MAEB in mitigating rider injuries is not well understood, particularly in scenarios where the efficacy of standard MAEB is limited because the rider is manually braking. The purpose of this study was first, to assess the injury mitigation potential of MAEB and second, to test MAEB as an enhanced braking system applied in circumstances where the rider is braking before a crash. The findings estimate the degree to which MAEB could mitigate motorcycle crashes and reduce injury risks for motorcyclists.
2021 – “Field Testing the Applicability of Motorcycle Autonomous Emergency Braking (MAEB) During Pre-crash Avoidance Maneuver” – ABSTRACT
The objective of this paper is to assess the applicability of Motorcycle Autonomous Emergency Braking (MAEB) activation during lateral avoidance maneuver and to estimate its benefits in this scenario. The objective of this paper is to assess the applicability of MAEB activation during lateral avoidance maneuver and to estimate its benefits in this scenario.
2019 – “Loss of Control Prediction for Motorcycles during Emergency Braking Maneuvers Using a Supervised Learning Algorithm”
The most common evasive maneuver among motorcycle riders and one of the most complicated to perform in emergency situations is braking. Because of the inherent instability of motorcycles, motorcycle crashes are frequently caused by loss of control performing braking as an evasive maneuver. Understanding the motion conditions that lead riders to start losing control is essential for defining countermeasures capable of minimizing the risk of this type of crashes. This paper provides predictive models to classify unsafe loss of control braking maneuvers on a straight line before becoming irreversibly unstable. The loss of control predictive models developed may provide support to: (a) active safety systems developments; and (b) training actions aiming to improve rider’s skills with objective indicators of the controllability of the braking maneuver.
Up to 17% of all motorcycle accidents occur when the rider is maneuvering through a curve and the main cause of curve accidents can be attributed to inappropriate speed and wrong intra-lane position of the motorcycle. Existing curve warning systems lack crucial state estimation components and do not scale well. We propose a new type of road curvature warning system for motorcycles, combining the latest advances in computer vision, optimal control and mapping technologies to alleviate these shortcomings.
This is a U. S. DOT sponsored report. Intelligent Transportation Systems (ITS) present an array of promising ways to improve motorcycle safety. While ITS technologies have predominantly targeted automobiles and commercial vehicles, little has been done to specifically address motorcycles or motorcycle safety. To help rectify this, this project surveyed a wide range of ITS technologies with potential relevance to motorcycles; analyzed each technology’s current relevance to motorcycles and potential to improve motorcycle safety; and then further investigated those technologies with strong potential to improve motorcycle safety. The project employed a two-pronged methodology in its survey of ITS technologies, consisting of (1) a comprehensive literature review of over 40 categories of ITS with potential relevance to motorcycles and (2) interviews with leading practitioners representing a cross section of the motorcycle industry and community.
In comparison to the widespread advancement of safety-enhancing technologies for passenger vehicles, there has been only limited development of Intelligent Transport Systems (ITS) for motorcycles. This review from Monash University, Australia investigated and discusses ITS according to their likely safety benefits to motorcycle safety.
This report provides the results on an online survey of 61 motorcyclists who crashed between 2010 and 2015. The survey was carried out in 2016 focusing on motorcyclists who had crashed while riding a motorcycle fitted with Advanced (anti-lock) Braking Systems (ABS). The survey was a pilot study to identify specific issues relating to crashes involving motorcycles fitted with ABS. Although this pilot survey is a small sample, the wealth and depth of information provided by the motorcyclists who participated allows for a wide range of analysis of the details that resulted from the questionnaire and the responses.
Abstract describing a knowledge-based system of motorcycle safety (KBMS) was developed to assess the potential for various safety solutions to mitigate or avoid motorcycle crashes. Results revealed that automatic systems have the greatest potential to improve motorcycle safety
This study was conducted to determine whether adding in-vehicle technology to vehicles (not the motorcycle) resulted in increased driver awareness of motorcycles. The specific technology tested consisted of a warning light which illuminated on the vehicle’s instrument panel when the vehicle was near a motorcycle. Results showed that the in-vehicle technology significantly increased driver awareness of motorcycles
Doctoral thesis. The findings indicated that Motorcycle ABS reduced emergency care visits by 47%. The severity of the crashes that did occur was lower, which reduced the overall risk of sustaining impairing injuries, although leg injuries were not addressed to the same extent. It was also found that almost 90% of fatal crashes with ABS were upright. This result suggests that leg injuries can be addressed by motorcycle design. An example with a specific design (i.e. boxer-twin engine) was analyzed, showing that leg injuries were reduced by approximately 50%. Finally, it was found that the overall reduction of injury crashes with ABS ranged from 24% in Italy to 29% in Spain and 34% in Sweden.
2016 – “Does the Improved Stability Offered by Motorcycle Antilock Brakes (ABS) Make Sliding Crashes Less Common? In-depth Analysis of Fatal Crashes Involving Motorcycles Fitted with ABS”
Abstract. Though this research was based on a limited material, it confirmed that sliding fatal crashes are significantly decreased by ABS. These findings should be taken into account in the future design and testing of motorcycle-friendly road barriers and integrated protection systems.
Abstract. The results support the hypothesis that ABS is effective in reducing the crash risk in some crash types. However, it was found that the case-control approach does not incorporate all factors that might influence the overall effectiveness of ABS.
2015 -“Feasibility Study of Airbag Concept Applicable to Motorcycles without Sufficient Reaction Structure”
Abstract. Through the crash tests, beneficial protection effects of the airbag system were confirmed in particular impact configurations. No significant risk for the occupant due to the airbag was observed in the conducted crash tests. It was concluded that the proposed airbag system has feasibility to reduce rider injury in a collision of a motorcycle without sufficient reaction structure.
2015 – “The Combined Benefits of Motorcycle Antilock Braking Systems (ABS) in Preventing Crashes and Reducing Crash Severity”
Abstract. This article indicated that motorcycle ABS reduced impairing injuries, mostly due to fewer emergency care visits but also due to a reduction in crash severity, however, the lower extremities would be more exposed in a crash with ABS.
2015 – “Evaluation of the Effectiveness of Anti-Lock Braking Systems on Motorcycle Safety in Australia”
Findings showed the presence of ABS on the studied motorcycles resulted in a 33% in a reduction in all injuries in relevant crash types and 39% reduction in severe injuries.
2015 – “Effectiveness of Antilock-Brakes (ABS) on Motorcycles in Reducing Crashes, a Multi-national Study”
This study set out to evaluate the effectiveness of Antilock-Brakes (ABS) on motorcycles in reducing real-life crashes. The effectiveness of motorcycle ABS in reducing injury crashes ranged from 24% in Italy to 29% in Spain and 34% in Sweden. The reduction of severe and fatal crashes was even greater, at 34% and 42% in Spain and Sweden, respectively. At this stage, there are more than sufficient scientific-based proofs to support the implementation of ABS on all motorcycles, even light ones.
Discussion paper. Discussion of the research conducted by Monash University Accident Research Centre on the Evaluation of the Effectiveness of Motorcycle Anti-Lock Braking Systems on Motorcycle Safety in Australia.
2014 – “Further Development of Motorcycle Autonomous Emergency Braking (MAEB), What Can In-depth Studies Tell Us – A Multinational Study”
Author's Original Manuscript of an article published in Traffic Injury Prevention. This research is the first attempt to evaluate MAEB with simulations on a broad range of crash scenarios using in-depth data. The results give further insights into the feasibility of MAEB in different speed ranges. It is clear then that MAEB is a promising technology that warrants further attention by researchers, manufacturers and regulators
ABS was associated with a 31 percent reduction in the rate of fatal motorcycle crashes per 10,000 registered vehicle years. Conclusions: Further evidence shows that ABS is highly effective in preventing fatal motorcycle crashes.
2013 – “Assessing the Potential Benefits of the Motorcycle Autonomous Emergency Braking (MAEB) using Detailed Crash Reconstructions”
The MAEB proved to be beneficial in a large number of cases. When applicable, the benefits of the system were in line with the expected values. When not applicable, there was no clear evidence of an increased risk for the rider due to the system.
A giant leap towards safer motorcycles is the application of ABS. Even today’s systems that are still improvable would be socio-economically sensible with a benefit-cost-ratio of more than four. The impact on accident figures is estimated to be at least a 10% reduction. Concluding from these results, all motorcycles should be equipped with ABS. Further systems like active stabilization of Motorcycles are not possible and will very likely never be in the future. Therefore further development, evolution and optimization of ABS and TCS are required as a basis for other advanced safety systems.
The rate of fatal motorcycle crashes per 10,000 registered vehicle years was 37 percent lower for ABS models than for their non-ABS versions. ABS appears to be highly effective in preventing fatal motorcycle crashes based on some early adopters of motorcycle ABS technology.
2009 -“Effectiveness Evaluation of Antilock Brake Systems (ABS) for Motorcycles in Real-world Accident Scenarios
A paper presented at proceedings of the 21st International Technical Conference on the Enhanced Safety of Vehicles. Several real accident scenarios without ABS were analyzed under the condition that an ABS system would have been installed on the motorbike. With such an approach the difference in the accident consequences with and without ABS can be observed. In addition a variation in the ABS control has been accomplished by considering different brake control systems developed by CONTI, like partial and full integral brake systems as well as systems with advanced driver-assistance functions (ADAS).
2009 – “The Effectiveness of Antilock Brake Systems on Motorcycles in Reducing Real-life Crashes and Injuries”
Findings show that head-on collisions were the least ABS-affected crash types and collisions at intersections the most influenced. Induced exposure analysis showed that the overall effectiveness of ABS was 38 percent on all crashes with injuries and 48 percent on all severe and fatal crashes, with a minimum effectiveness of 11 and 17 percent, respectively. The study recommends the fitment of ABS on all new motorcycles as soon as possible and that customer’s only purchase motorcycles with ABS.
Significant reductions in collision claim frequencies and overall losses were found for motorcycles equipped with ABS. This study also includes an analysis of medical payment coverage, which typically pays for operator injuries, and bodily injury liability coverage, which typically pays for passenger injuries.
A paper presented at the proceedings of the 21st International Technical Conference on Enhanced Safety of Vehicles. Studies were carried out to examine the safety potential of Anti-Lock Braking Systems (ABS) and Vehicle Stability Control (VSC) for motorcycles by means of accident analysis, driving tests and economical as well as technical assessment of the systems. In principle, ABS is seen to have the potential to reduce fatalities among motorcycle riders by about 10 %. The potential for future dynamic control systems is estimated very low.
The motorcycle accidents influenced by this system are only a small portion of the mentioned accidents, so as a result of this study, the potential for future vehicle dynamic control systems that help prevent non-braking cornering accidents is estimated quite low.
2006 – “A Comparison of Stopping Distance Performance for Motorcycles Equipped With ABS, CBS and Conventional Hydraulic Brake Systems”
A paper presented at 2006 International Motorcycle Safety Conference. In general, the test results demonstrated an improvement in braking performance with the use of ABS, whether braking on a dry or wet surface even compared with the best stops obtained without ABS. Without ABS, the rider required numerous attempts to approach the maximum deceleration performance of the motorcycle. With the use of ABS, however, the rider was able to quickly obtain consistent maximum deceleration results, whether the vehicle was loaded or lightly loaded.
The average experienced motorcycle driver and novice drivers as well do not achieve braking deceleration suitable for road traffic. But if they use a motorcycle fitted with ABS after having received adequate instruction, they do. ABS should be mandatory equipment for every powered two-wheeler.
To date, an airbag prototype which is beneficial and not injurious to riders of all sizes has not yet been found. Much of this research has been exploratory and involves the development of various airbag concepts as well as improvement and standardization of the research methodology used to evaluate such prototype systems.