Road Rules Usually Cover Small Cycles

Sep 10, 2025

In recent years, there has been a dramatic increase in the sale of mopeds, motor scooters, all-terrain cycles, pedal bicycles with helper motors and similar small two- and three-wheel vehicles. Our need for fuel economy and our interest in recreation largely explain the popularity of the small motorized vehicles.

Unfortunately, the applicability of traffic laws to these motor vehicles is confusing.  Even lawyers, police officers and traffic court judges are sometimes unsure which laws apply.

Generally, the rules of the road govern all vehicles, including these small motorized ones. For example, if you run a red light or drive while intoxicated on any vehicle, you can be issued a citation or be arrested.

A driver’s license is required to operate any two- or three-wheel motorized vehicle on the street. Specifically, a motorcycle driver’s license is required for everything but a pedal bicycle with helper motor. For a pedal bicycle, any class of driver’s license will suffice.

When riding a motorized two- or three-wheel vehicle, except for pedal bicycles with helper motors, both operators and passengers who are younger than 18 must wear helmets and operators also must have eye protection.  These protection devices should be worn by every operator.

Pedal bicycles with helper motors do not need license plates, nor do they need to be tested for emissions. They must, however, be registered with the Motor Vehicle Division. For street use, all other motorized cycles must be tested for emissions, equipped with license plates and registered.

Arizona’s mandatory insurance law requires a vehicle to be insured if it meets any one of these requirements:

  • It has a motor that exceeds 5 horsepower
  • It is designed to be operated at more than 25 miles per hour
  • It has a piston displacement of more than 50 cubic centimeters

Although some of the laws that may apply to small motorized cycles are unclear, others are not. If you own or operate one of these cycles, you should be sure to comply with the legal requirements described here. When operating your cycle on the street, you must obey traffic regulations, as if you were driving a car.