Motorcycles are smaller and more maneuverable, offering distinct advantages, including reduced emissions, traffic and parking congestion, simply by taking up less space. Most of the reasons motorcycles are prevented from sharing lanes have little evidence to support them.
A 2015 study involving the University of California, Berkeley and the California Highway Patrol examined 7,836 motorcycle crashes, with 1,163 occurring while the rider was lane sharing. The study found that lane-sharing motorcyclists wore better helmets and were substantially less likely to suffer injuries than other motorcyclists. They were also more likely to be involved in weekday collisions during peak traffic times, aka rush hour.
According to the National Highway Traffic Safety Administration, rear-end collisions make up 40 percent of all accidents, which is a much higher injury risk factor for motorcyclists. Lane-sharing riders are less likely to be rear-ended, but more likely to rear-end another vehicle, with less injury. An argument against sharing lanes is that it increases risk. In addition to proximity reducing avoidance options, motorcyclists must be more aware of road surface issues. But the risk of being run over by distracted drivers is also substantial. Allowing lane sharing doesn’t force anyone to participate, instead it offers a choice between the risks of being in full control or at the mercy of others.
Another common complaint is queue jumping; a belief that it is unfair for any vehicle to move faster. But the longer lane sharing is allowed, the more tolerant drivers become, even moving out of the way. When motorcycles pass by, it removes them from the queue altogether, rather than sitting in line, increasing delays with every other vehicle.
After bikes maneuver ahead of traffic, they accelerate away quickly, speeding up overall traffic flow. Bicycle, bus and HOV lanes already allow other vehicles to pass automobiles unhindered, setting a precedent. Lane-sharing legislation should start by opening reserved lanes to motorcycles and allowing filtering to the front at stoplights.
A 2012 study by Belgian research firm Transport & Mobility Leuven found that if 10 percent of drivers switched to motorcycles and filtered through traffic, travel time for the remaining vehicles would decrease by 40 percent. Additionally, if 25 percent switched from four wheels to two, it would completely eliminate congestion. Finally, it would lower overall vehicle emissions at least 6 percent, by reducing the amount of time every vehicle spends idling. That’s not only environmentally conscious, it saves everyone money on fuel. Drivers who convert to riders become part of the solution instead of the problem.
Some drivers argue that they cannot see motorcycles sharing lanes, but they don’t see us anyway. The ability to quickly maneuver around traffic allows for better positioning, which can increase visibility to others and allow the rider to see traffic much better than being stuck behind a truck.
Another argument is liability, but sharing lanes doesn’t forgive stupidity or lawbreaking. Motorcyclists must still obey traffic signals, speed limits and other rules of the road. A motorcyclist can still be at fault, liable and cited or prosecuted.
Speed is a major factor in injuries while lane sharing. The Berkeley study found there was no rise in the severity of injuries up to a 15-mph differential between the motorcycle and surrounding traffic. However, when traffic is moving at full speed, there is no incentive to share lanes at all. In other words, passing another vehicle is already illegal if traffic is traveling at the posted speed limit.
Sharing lanes is extremely valuable to all road users when traffic is slow or stopped, which is also when it is safest to do so. Lane sharing is statistically less risky for motorcyclists below 30 mph and not more than 10 mph above the speed of traffic.