Street Racing Cars For Sale

Above Jake Lyall's RIOT wheel at the 2003 Burning Man Festival.
This chunky 1100-pound machine is Jake Lyall's RIOT (Re-Invention Of The) wheel. Lyall's monowheel is unusual because it does not use the rider's weight to provide the reaction to the engine's thrust on the wheel. Instead the rider is outside, and the reaction is given by a lead-weighted Honda 80cc 4-stroke scooter engine suspended from a central shaft, driving through a sprocket attached to the wheel spokes. A separate 450-pound counterweight keeps the rider hovering above the ground at the front. Steering is done partly by precessing a 65-pound gyroscope to give yaw, and partly by the rider shifting his weight.
read about, and check out the cut away drawings of it http://douglas-self.com/MUSEUM/TRANSPORT/motorwhl/motorwhl5.htm

Via: http://ottonero.blogspot.com/2009_09_01_archive.html