One of the distinguishing features is that they don't need valves to operate. That's to say, the Wankel rotary engine design doesn't have valves -- but quite a few rotary engine designs have ...

Solid design, but what if you turned it all inside out? That’s more or less the concept behind this rotary engine. It is a “monosoupape,” or single valve, design that was mainly used for ...

So far, the rotary valve engines have really only made ... This being the case, engineering work is still being done on the basic design of the engines that power our cars, motorcycles and scooters.