How about a bicycle that uses an electric motor hidden inside the frame ... There's apparently some sort of controversy in professional racing right now regarding a rider using "doped bicycle ...

Two men on dirt bikes escaped police after a chase through surface streets and freeways in Los Angeles County, waving at police and news helicopters. No one was arrested.

Little is known about the incidence of injury to race track motor-cyclists and car drivers ... However, the anatomical distribution of injury caused by motor-bike accidents is similar to that found on ...