The law has a precise definition of what constitutes a bicycle. A bicycle must be self-propelled and not have the assistance of any mechanical device. For example, if a bike has a motor which is powered by gas or battery, that would not be considered a bicycle. It must have two wheels and be self-propelled in order to be considered a bicycle under the law. If a bicyclist is riding on the road, they are held to the same standards as automobiles. Bike riders must obey the rules of the road.