 As the wheels necessarily come at a weight penalty it is often possible to exchange them with standard wheels to match the capabilities of the wheelchair to the current activity.Mobility scooters share some features with powerchairs, but primarily address a different market segment, people with a limited ability to walk, but who might not otherwise consider themselves disabled.Smaller mobility scooters are typically three wheeled, with a base on which is mounted a basic seat at the rear, with a control tiller at the front.