The Wankel, or rotary, engine was made famous in the twowheeled world by the JPSbacked Nortons raced by Steve Spray and Trevor Nation. However, the Wankel engine concept was nothing new and Norton had been building one for nearly 20 years at this point. Originally designed by German engineer Felix Wankel in 1929, his style of motor is very different to a conventional engine. Despite using the same four-cycles (intake, compression, ignition, exhaust), where on a normal motor these happen above a moving piston in a barrel, in a Wankel they happen in the space between a threesided symmetrical rotor. A shaft passes through the centre of the engine and the rotor rotates around this, creating the four distinct cycles against the inside of the motor as it orbits around. In one 360-degree turn of the rotor the four-cycles happen, making it more efficient than a conventional engine, which needs two crank rotations to achieve the same cycles. Why didn’t they catch on? The Wankel isn’t a very clean motor, is tricky and expensive to manufacture and can be unreliable, so it quickly went out of fashion despite its ability to rev and produce high power outputs.