A pedal moped is a two-wheeled, motorized vehicle with pedals. The pedals serve two functions — auxiliary propulsion and a mechanical starting mechanism for the motor, similar to the old-style hand cranks on early automobiles. The term moped itself is a combination of the words "motor" and "pedal" and originally, all mopeds were vehicles of this type although many variations existed. A Pedal moped may be designed with the pedal system connected to the engine or independent of it.
The first mopeds were low-powered motorcycles that were fitted with pedals as a source of auxiliary power for steep hills. The pedals were also regarded as an improvement over the prevalent starting procedure for most early motorcycles which consisted of the user running along side the motorcycle as he pushed started it and then jumped on to ride away. Engine technology improved rapidly and the pedals were no longer necessary for motive power by 1920, but inexpensive mopeds continued to be designed with them for starting purposes and for use as motive power instead of the engine when necessary.
Today, the term moped has come to be defined in a broader sense and is usually applied to two-wheeled motorized vehicles with a maximum engine displacement of 3 cubic inches (49 cc) and a maximum speed of 30 mph (50 kph), although there is not an international standard and the use of the term may vary in different parts of the world.
Governments around the world have legally defined the term moped in many ways. In some areas, the restrictions on displacement, maximum speed or number of wheels may vary. Some jurisdictions have created another classification designated as an autocycle which may legally defined as a moped in other areas, creating some confusion over terminology. Some of these designs are of the pedal moped type.
Modern mopeds may resemble motorcycles, which are called step-over types. Mopeds which resemble scooters are called step-through types. The main difference is the lack of a structural component of the frame that usually extends from the area near the seat to the front post near the handlebars. A moped of either style, if outfitted with pedals, may be properly called a pedal moped.
Some moped designs with pedals have an engine that is not connected to these pedals. Some of these vehicles are nothing more than a standard bicycle with an engine attached. Many designs of this type have been produced by various manufacturers for decades; some have an engine mounted on the front wheel, some on the rear wheel. The pedals for these mopeds are purely for motive power when desired or needed. Kits are available from several manufacturers that will allow the conversion of a bicycle to a pedal moped.