For the purpose of this subchapter, the following definitions shall apply unless the context clearly indicates or requires a different meaning.
MOTOR SCOOTER and MOTORCYCLE. Every vehicle or device which is self-propelled, which is not moved by human power, which does not derive its power from overhead wires, and is not used exclusively upon stationary rails or tracks, and, in, upon, or by which any person or property may be drawn upon an alley, street or highway, having a saddle for the use of the rider and designed to travel on not more than three wheels in contact with the ground, including bicycles with motor attached, but excluding a farm tractor.
('72 Code, § 715:00)