As the name implies, the hub motor is a motor integrated into the hub cylinder, which converts electrical energy into mechanical energy when the motor is energized, thereby spinning the wheels and driving the vehicle forward.

There are two types of hub motors: geared hub motors and gearless hub motors.

Geared hub motors were earlier limited by precision and material, which can cause friction due to lack of precision, which can cause problems like noise and wear. With the development of industrial technology, most of the geared hub motors are now very well made, which you don't have to worry about.

And when the electric vehicle is powered off or the battery is dead, the internal design of the geared hub motor has a clutch device that makes the resistance when the vehicle is gliding or human pedaling less than the resistance of a gearless hub motor in the same situation. Therefore, it is widely used by electric vehicle manufacturers.

Gearless hub motors have a more traditional internal structure with no replicated planetary gear reduction, relying directly on electromagnetic conversion to generate mechanical energy to drive an electric vehicle.

Gearless hub motors are direct-drive and generally have no internal clutch, so they also need to overcome electromagnetic resistance when riding without power, but because of this, hub motors of this construction can convert kinetic energy into electrical energy to be stored in the battery during downhill rides.

Not all gearless hub motors are actually capable of recovering kinetic energy, and while this sounds like a great idea, its practical application would be very costly and would increase its complexity more than it would pay for itself.