The Wankel engine's design is much simpler than that of a piston engine, with fewer moving parts. It has a rotor, rotating in an oval chamber. When the engine is running, all its cycles are going on at the same time. The Wankel engine is efficient, but it uses more fuel than a piston engine. It was named for its designer, Felix Wankel, a German scientist.

1. The fuel air mixture is taken into the chamber.

2. The mixture is compressed and ignited by the spark plug.

3. The burning mixture expands and pushes the rotor around. This turns the crankshaft.

4. Burned gas is forced out through the exhaust.