Abstract: The wheeled vehicle drive apparatus attaches to an existing wheeled vehicle, such as a wheelchair or shopping cart and uses the existing wheels of the vehicle for drive. The circular drive case provides efficient space utilization in typically cramped confines in and around a wheeled vehicle. The two-piece case allows easy service and parts replacement. Two levers are provided for attachment to existing vehicle handles, with one providing throttle speed control and one providing breaking. Braking is provided internal to the drive case, thereby negating the need for an external brake on the vehicle. Positive engagement with vehicle wheels is assured by the adapters with adapter lugs.