A big wheel motive power source is provided. The big wheel motive power source comprises a large mass wheel capable of rotation and having a mass comprising at least one-third the weight of a vehicle in which it is located, or at least twice the weight of a conventional engine for that vehicle. A small horsepower, continuously running engine is operably connected to the large mass wheel and generates the rotation of large mass wheel. The large mass wheel may be further connected to at least one driven wheel, whereby the rotation of the large mass wheel provides a primary motive power source for a vehicle. A ratchet-type worm engaged drive, a control system, and a exhaust removal system are also disclosed for use with the present inventive device.