Rocket on two wheels

Engineer's bike goes 0 to 60 mph in five seconds

In place of synthetic rubber fuel, however, the bike uses ordinary roofing tar. To ignite it, Pickens placed a model-rocket motor inside the engine. A button on the handlebar fires the model-rocket motor, which in turn sets off Pickens's larger motor by lighting the roofing-tar fuel.
http://www.cnn.com/2006/TECH/01/24/rocket.bike/index.html