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 ...

This means it is a reciprocating rotary engine. Yeah, weird stuff. The camshaft is also centrally located in the crankcase and still runs at 50-percent crankshaft speed but only actuates one valve ...

Further proof of this truth comes by way of Taiwanese scooter manufacture PGO, which has partnered up with RCV Engine Ltd. of the U.K. The two firms are working on rotary valve technology for ...