Motorcycles

Riding a motorcycle is inherently riskier than driving a car. Motorcycles are harder for other drivers to see and less stable than passenger vehicles. Without the protection of an enclosed occupant compartment, motorcyclists are also more likely to be injured or killed when they crash.

A proper helmet is the most important piece of motorcycle safety equipment. Unhelmeted riders are much more likely to be killed or suffer traumatic brain injuries in the event of a crash. Nevertheless, only 17 states and the District of Columbia require all riders to wear them.

An antilock braking system (ABS) reduces the risk of a motorcycle crash. By preventing skidding that can cause a serious fall, ABS substantially reduces fatality rates for equipped bikes. Despite this benefit, the technology is not required on motorcycles sold in the U.S.

Some kinds of motorcycles are riskier than others. Equipped with high-horsepower engines and built on racing platforms, supersport motorcycles have much higher driver death rates than other types.

A total of 6,222 motorcyclists were killed in crashes in 2022, nearly triple the number in 1997 and 23% higher than in 2019. This is the highest number of motorcyclist crash deaths in a single year since the National Highway Traffic Safety Administration (NHTSA) began collecting fatal motor vehicle crash data in 1975.

Motorcyclists accounted for 15% of all crash deaths in 2022. However, per mile traveled, the number of deaths on motorcycles in the U.S. was nearly 29 times the number in passenger vehicles.

Motorcycle owners have gotten older in recent decades. The typical motorcycle owner in 2018 was 50 years old (Motorcycle Industry Council, 2019). That contrasts with 1980, when the typical owner was 27 (Motorcycle Industry Council, Motorcycle Statistical Annual, 2000). In 1982, 3% of fatally injured motorcyclists were 50 and older; in 2022 over a third were.

More women are riding motorcycles. Today, 19% of motorcycle owners are women, compared with 6% in 1990 (Motorcycle Industry Council, 2019). Despite that increase, women made up only 4% of motorcycle drivers killed in 2022 crashes, though they accounted for 91% of the passengers who died.

Helmets decrease the likelihood of death and brain injuries from motorcycle crashes.

• Studies have found that helmets reduce the risk of death by 37%-42% (NHTSA 2008; Norvell & Cummings, 2002).
• Unhelmeted motorcyclists are 3 times more likely than helmeted riders to suffer traumatic brain injuries (NHTSA, 2008).

Helmets that are sold as head protection for motorcyclists are required to meet federal performance standards. Helmets that don’t meet the standards are known as “novelty helmets.” A recent study found riders using novelty helmets were about twice as likely to die in crashes than riders wearing certified, full-face helmets (Rice et al., 2017).

Certified helmets are available in different styles, including half-coverage (covering the upper half of the head, generally above the ears), open-face and full-face. One study found that crash-involved riders wearing half-coverage helmets were twice as likely to suffer traumatic brain injuries than riders wearing open-face or full-face helmets (Yu et al., 2011).

Some people claim that helmets increase the risk of neck injury and reduce peripheral vision and hearing. More than a dozen studies have refuted the claim that helmets cause neck injuries (for example, Orsay et al., 1994; Crompton et al., 2011).

A 1994 study found that wearing helmets does not restrict the ability to hear horn signals or to see a vehicle in an adjacent lane prior to initiating a lane change (McKnight & McKnight, 1994).

Other protective gear specifically designed for motorcyclist protection, such as jackets, pants, gloves and boots, have been shown to improve post-crash health outcomes after other types of severe injuries (de Rome et al., 2012).

Universal helmet laws — state laws that require helmet use for all riders (operators and passengers) — are extremely effective.

In 2022, 93% of motorcyclists observed in states with universal helmet laws were wearing helmets. In states without such laws, helmet use was 64% (NHTSA, 2023). Use of helmets judged to be compliant with federal safety regulations was 82% among motorcyclists in states with universal helmet laws and 56% in states without such laws.

Helmet laws that apply only to young riders are virtually impossible to enforce.

Decades ago, the federal government required states to pass universal helmet laws in order to be eligible for certain safety and highway construction funds. As a result, all but three states had such laws in 1975. Once this incentive was removed in 1976, states began to repeal or weaken their laws.

Today, only 17 states and the District of Columbia have universal helmet laws, and 30 states have laws covering some riders, usually people younger than 18. Three states (Illinois, Iowa and New Hampshire) do not have any helmet requirements.

Motorcycle helmet use laws by state in detail

Over 22,000 motorcyclists are estimated to have died in crashes during 1976-2022 as a result of lower helmet use in states without universal helmet laws (Teoh, 2024). This represents 11 percent of all motorcyclist fatalities during these years.

By state, the largest number of lives lost – 2,536 – was in California, primarily due to its large population and long riding season. However, California has required all riders to wear helmets since 1992, so this number stopped growing at that time. Other states with high numbers of deaths due to lax helmet laws include Texas (2,490), Florida (1,786), Illinois (1,738), Ohio (1,651), Indiana (1,151), and South Carolina (1,000). Those states still allow unhelmeted riding, so their toll will continue to rise.

Various states have enacted and repealed universal helmet laws between 1976 and today. When states enact such laws, deaths, injuries and medical costs go down. When they repeal them, the reverse usually happens.

• When California’s helmet use law covering all riders took effect in 1992, the number of motorcyclist fatalities decreased 37% (Kraus et al., 1994).
• Nebraska reinstated a helmet law in 1989, after repealing an earlier law in 1977. The state then saw a 22% reduction in serious head injuries among motorcyclists (Muelleman et al.,1992). Acute medical hospital charges for injured motorcyclists declined 38%. Despite these benefits, Nebraska has weakened its helmet law to exempt riders 21 and older who submit proof of completing a rider training course. This takes effect Jan. 1, 2024.
• From 1968 to 1977, Texas had a universal helmet use law estimated to have saved 650 lives, but the law was amended in 1977 to apply only to riders younger than 18. The weakened law coincided with a 35% increase in motorcyclist fatalities. Texas reinstated its helmet law for all motorcyclists in 1989. Serious injury crashes per registered motorcycle decreased 11% (Mounce et al., 1992). But in 1997, Texas again weakened its helmet law, requiring helmets only for riders younger than 21. Operator fatalities increased 31% in the first full year following the repeal (Preusser et al., 2000).
• Kentucky repealed its universal helmet law in 1998, followed by Louisiana in 1999. Motorcyclist deaths quickly increased in these states by 50% and 100%, respectively (Ulmer & Preusser, 2003).
• In 2000, Florida’s universal helmet law was weakened to exempt riders 21 and older who have at least $10,000 of medical insurance coverage. An Institute study found that the motorcyclist death rate in Florida increased by about 25% after the state weakened its helmet law (Kyrychenko & McCartt, 2006). Hospital admissions of motorcyclists with head injuries increased 82% during the 30 months following the law change (Ulmer & Northrop, 2005). The average inflation-adjusted cost of treating these injuries went up from about $34,500 before the helmet law was weakened to nearly $40,000 after — 4 times the $10,000 minimum medical insurance requirement.
• Michigan weakened its universal helmet law in 2012 to exempt riders 21 and older who have at least $20,000 of medical insurance coverage and have either passed a motorcycle safety course or held a motorcycle license endorsement for at least two years. The change was associated with a 22% increase in the average insurance payment for injuries to motorcyclists (HLDI, 2013), as well as increased head injuries and neurological interventions, but no significant change in deaths (Carter et al., 2017).

Motorcycles vary widely in their design, the type of rider they appeal to and their crash risk.

Street-legal motorcycles can be grouped into 10 different classes in a system developed by HLDI.

Cruisers mimic the style of American motorcycles from the 1930s to 1960s, such as Harley-Davidsons and Indians.

Standards have basic designs and upright riding positions, with low power-to-weight ratios that result in a user-friendly motorcycle.

Supersports are consumer versions of racing motorcycles. Reduced weight and increased power allow for quick acceleration, nimble handling and high speeds.

Sport motorcycles are closely related to supersports. Sport bikes are capable of high speeds but typically don’t have the acceleration, stability and handling of supersports.

Unclad sport motorcycles are similar to sport bikes and supersports in design and performance but without plastic body fairings.

Sport-touring motorcycles are similar to sport bikes but tend to be heavier and equipped with touring features such as saddlebags, a rear trunk and larger seats. Typically, they have more substantial windshields and wind-deflecting fairings than sport bikes.

Touring motorcycles have big engines and fuel tanks plus room to haul luggage. They’re often outfitted with antilock brakes, audio systems and cruise control.

Scooters have small wheels, automatic transmissions and small engines, but larger scooters are becoming more popular.

Cruisers are the largest class of bikes. They accounted for 38% of registrations in 2023 (Teoh, 2023).

Registration-based death rates indicate that drivers of cruisers, standards, touring and sport-touring motorcycles have the lowest death rates.

Supersport motorcycles make up a small fraction of registered motorcycles, but their riders are overrepresented in fatal crashes. A 2010 IIHS study found that the driver death rate per 10,000 registered motorcycles for supersports was about 4 times as high as the rate for motorcyclists who rode cruisers or standards (Teoh & Campbell, 2010).

Studies of fatal crashes, insurance claims and test track performance all confirm the importance of antilock braking systems (ABS) for motorcycles.

The rate of fatal crashes is 22% lower for motorcycles equipped with optional ABS than for those same models without ABS (Teoh, 2021).

Collision insurance claims for motorcycles with ABS are filed 21% less frequently than for motorcycles without it — 28% when the ABS bikes have combined brake controls (Basch et al., 2015).

On the test track, both new and experienced riders stop more quickly with antilock brakes. Stopping distances improve on wet and dry surfaces alike (Austrian Road Safety Board, 2004; Green, 2006).

Braking on a motorcycle isn’t the same as braking in a car. Most motorcycles have separate brake controls for the front and rear wheels, and either wheel can lock up during hard braking. On a car, a lockup might result in a skid. On a motorcycle, it often means a serious fall.

Even skilled riders may accidentally overapply the brakes if a driver cuts them off or if road surfaces become unexpectedly slick. ABS allows riders to brake fully without fear of locking up. The system automatically reduces brake pressure when a lockup is about to occur and increases it again after traction is restored. This cycle repeats many times per second until an imminent lockup is no longer detected.

How ABS works

An antilock braking system works by constantly measuring wheel speed. One common way to do this is with a small grooved ring near the brake disc often called a tone wheel. The wheel speed sensor sends the tone wheel readings to the ABS unit, which can determine whether the wheel is about to stop rotating. If it is, wheel speed information is used to adjust the pressure from the brake cylinder on the brake caliper multiple times per second.

ABS doesn’t affect normal braking — you notice it only in an emergency. Both conventional braking systems and combined braking systems, which link one or both controls to both wheels, can have ABS.

Over the past decade, all member states of the European Union as well as Australia, Brazil, India, Japan, New Zealand, Taiwan, Thailand and the United Kingdom have mandated that many types of motorcycles be equipped with ABS. Although there is no requirement in the U.S., the technology is widely available. Among 2023 motorcycles, 64% of models come with standard ABS, and another 18% offer it as an option.