So, How Does It Work? The Wankel Rotary Combustion Engine Theory, Design, and Principles of Operation Internal combustion engine: fuel air mixture ignites and the explosion directly drives the engine internally. Four phase Otto Cycle engine: intake, compression, power, exhaust. Three main moving parts in most RC engines: 2 rotors and the eccentric shaft. These rotate continuously in a single direction. They do not jerk backwards and forwards. These are surrounded by the peripheral housing where the rotor tip traces out an epitroichoid curve. The Wankel RC Engine is an Otto Cycle Engine (Four "Stroke") The RCE has four phases in its combustion cycle whi