The drive train is an integral part of the base unit and provides either front- or rear- wheel drive for the scooter. Front-wheel drive is usually found on smaller scooters designed primarily to be used indoors or outdoors on flat, paved surfaces. The motor of the front-wheel drive scooter is located over the front wheel and drives only that wheel. Because of the motor and wheel configuration, front-wheel drive scooters are usually direct-drive units, eliminating chains and belts. However, this also means that the front wheel pulls the weight of the unit and the rider. Consequently, these types of scooters have a lesser capacity to move their load than do rear-wheel drive models, and are therefore less capable of handling hills, curb cuts, and other outdoor terrain. This is compounded by the fact that front-wheel drive models generally have smaller motors, causing them to have a shorter range, less speed and power, and a smaller rider weight capacity.
Rear-wheel drive scooters are powered by motors connected to the rear axle, either via a chain, a belt, a transaxle unit, or some combination. Because the scooter is driven by the rear wheels, they push the combined weight of the unit and the rider, rather than pull it. The combined weight of the rider, the motor, and the batteries over the rear wheels, generally create better traction than that usually provided by front-wheel drive models. The increased traction combined with the more powerful motors used on rear-wheel drive scooters results in better climbing ability. The units also have a greater maximum speed, a longer traveling range between battery charges, and a larger rider weight capacity. These scooters have a wider wheel base and a greater overall length, making them less maneuverable and rendering some models unsuitable for indoor use. They may also be too large for van or bus lifts.