The Science – and Politics – of Bicycling Driving


Bicycles are human-powered vehicles capable of significant speed. Bicycle driving is the operation of a bicycle according to the laws and scientific principles that apply to the operators of all vehicles on public roads. These “Rules of the Road” represent our society’s best understanding of how to minimize collisions while maximizing mobility and access for all citizens. Bicyclists have the legal rights and duties of drivers of vehicles when operating on public roadways according to traffic laws in every US state. Bicycle drivers who operate according to traffic rules for vehicles enjoy travel that is much faster and much safer than those bicyclists who do not.

Despite the history, laws, and traffic science that support vehicular-style operation of bicycles, there is a common belief that bicyclists cannot travel safely with motor vehicles. People who believe bicyclists are inferior to other road users often want to prohibit bicyclists from using roadways, and force cyclists to operate at slow speeds among pedestrians on sidewalks and trails. The motives for this prohibition are to improve convenience for motorists traveling on inadequate roads and to reduce the level of traffic competence currently expected of lawful drivers of motor vehicles. Such changes would drastically increase the dangers and reduce the convenience of travel by bicycle, as has been demonstrated everywhere it has been tried.

Many well-meaning groups, who believe they are acting on behalf of cyclists’ best interests, wish to add special markings to roads and change the Rules of the Road in order to channelize traffic by vehicle type. The motives for these changes are to increase the political visibility of bicycling and reduce the level of traffic competence currently expected of lawful bicycle drivers. But such markings and law changes have not been scientifically shown to improve conditions for cyclists, and can actually make cycling more dangerous by increasing the complexity of traffic movements and violating the scientific principles of crash prevention that led to the existing Rules of the Road. If anything is to be done to improve conditions for cyclists and the motorists who share the roads with them, such actions should be based on scientifically sound principles known to reduce collisions while preserving cyclists’ right to travel efficiently. Treating cyclists as drivers of vehicles is the most successful and feasible approach known, yet much of the treatment of bicycling and bicycle operators in the United States has been based on the assumption that cyclists are inferior users of roadways. It is long past time to debunk this myth in favor of a scientifically and constitutionally sound approach that provides for the safety and convenience of both motorists and cyclists.

The basic principles that all drivers of vehicles follow in order to prevent collisions are listed below:


  • First come, first served. Each driver on the road is entitled to a “safety zone”, i.e. the space their vehicle occupies, plus reasonable clearance behind and to each side, and reasonable stopping distance in front of them. Other drivers who want to use this space must first yield to the driver already entitled to it. This principle applies both between intersections and at intersections. Yielding to traffic already on the road ahead requires driving slow enough to stop if traffic just beyond view is slow or stopped, and not following too closely in case traffic ahead stops suddenly.
  • Drive on the right-hand side of the roadway.
  • Yielding to crossing traffic. Drivers on less important roads, and that includes driveways and alleys, yield to traffic on more important roads. Yielding means looking and waiting until the movement can be made without violating the right of way of other highway users. Drivers turning left must also yield to thru traffic traveling in the opposite direction on the road. Traffic signals or signs often indicate which road has priority.
  • Yielding when moving laterally. Drivers who want to move laterally on the roadway must yield to traffic in their new line of travel. Yielding means looking behind, to the side, and in front and waiting until the movement can be made without violating the right of way of other highway users.
  • Destination positioning at intersections. Drivers must approach intersections (including driveways) in the proper position based on their destination. Right-turning drivers make their turns from the right side of the roadway, left-turning drivers do so from near the center line, and straight traffic goes between these positions.
  • Speed positioning between intersections. Drivers park on the rightmost edge of the highway. Drivers travel in a portion of right side of the road that is wide enough for them to maneuver safely and is available for thru-traffic. Where safe and practical, slower drivers operate far enough to the right to allow faster drivers to see past them and perhaps pass when it is safe to do so. Drivers should overtake slower traffic on the left, not on the right. (There are exceptions when vehicles are turning left, on multi-lane roads, and on one-way roads).


Following these six rules can prevent virtually all collisions on ordinary roads. The remaining special cases, mostly involving convenience enhancements, special facility designs, and resolution of ambiguities that arise when all parties have already stopped, are included in the traffic laws and taught as part of driver education. The Rules of the Road are simple to follow and limit the viewing area that a driver is required to watch except during special maneuvers that the driver expects. The Rules of the Road work for drivers of every vehicle type and make those drivers predictable to others.

Bicycle Driving, AKA Vehicular Cycling

A bicycle driver follows the vehicular Rules of the Road in order to safely and efficiently take advantage of the convenience of facilities designed for vehicular travel. The bicycle driver knows that she is an equal user of the roadway, and acts like it, cooperating with other drivers and asserting herself where necessary. Cycling down a street with wide lanes, she uses the right side of the lane to allow overtaking vehicles to pass easily, then looks behind to merge with traffic when approaching an intersection, and smoothly moves into the middle of the left turn lane in preparation for a left turn. She patiently awaits a green light before proceeding, looking carefully for other road users whose paths may conflict with hers as she turns. The bicycle driver cycles down a side street taking care to stay four feet away from parked cars in order to avoid being doored. On a street with lanes that are too narrow to safely share side-by side with a motorist, she drives in the middle of the lane to provide herself room to maneuver and to avoid being squeezed off the road. When traveling straight through an intersection, she uses the through lane, never the right-turn lane, and does not pass on the right side of other drivers who might turn right. On narrow two-lane roads with heavy traffic in each direction, she occasionally pulls off the road to disperse traffic if and when it backs up behind her. When cycling at night, she equips her bicycle with a white headlight in front and a bright red reflector, and perhaps a red light, on the back. A bicycle driver is not afraid of traffic; a bicycle driver is traffic.

Bicycling in travel lanes as the driver of a vehicle is standard operating procedure for many experienced cyclists in the United States. It complies with traffic law and the scientific principles of collision prevention. Most bicycling education programs run by cycling organizations, such as the League of American Bicyclists, teach this type of vehicular-style bicycle operation. In Britain, the vast majority of cyclists drive bicycles this way. Yet many – if not most – American teenagers and adults operate bicycles very differently. Many ride on sidewalks, or in the gutter, and often against traffic. They make left turns from the right edge of the road. They run red lights, ride straight from right turn lanes, and ride at night without a headlight, all while the police look the other way. When Americans do drive bicycles in a lawful, vehicular manner, they are sometimes harassed by police and motorists. Why is this? The reason is because popular American notions about appropriate behavior by adult bicyclists have nothing to do with science or the best interests of people who travel by bicycle. Instead, American perceptions of bicycle operation are based on a taboo promulgated for the convenience of motorists.