Wheel dated. The rim is the "outer edge of a wheel, holding the tire." It makes up the outer circular design of the wheel on which the inside edge of the tire is mounted on vehicles such as automobiles. For example, on a bicycle wheel the rim is a large hoop attached to the outer ends of the spokes of the wheel that holds the tire and tube. In the 1st millennium BCE an iron rim was introduced around the wooden wheels of chariots. The hub is the center of the wheel, and typically houses a bearing, and is where the
Wheel hub motor occurs as the rotor first begins to turn, which is why electric motors do not require a transmission. A gear-down arrangement may be needed, but unlike in a transmission normally paired with a combustion engine, no shifting is needed for electric motors. Wheel hub motors are increasingly common on electric bikes and electric scooters in some parts of the world, especially Asia. Compared with the conventional electric vehicle design with one motor situated centrally driving two (sometimes four) wheels by axles, the wheel motor arrangement has certain advantages and disadvantages: Cars with electronic control of brakes and acceleration provide more