Wankel engine http://www.keveney.com/Wankel.html
I hate to think how much that bike weighs.

Various manufactures (OK maybe 2) have made Wankel engined
bikes in production.

Norton
http://www.millville.org/workshops_f...ls/norton.html
They raced them seriously too IIRC.
I suspect that the Norton engine design may still be
in production. It used a novel rotor cooling
system where (IIRC) air was drawn through the inside
of the rotor. (Induction air? - surely not)

Suzuki
http://www.suzukicycles.org/RE5/RE5-Rotary.shtml

Sorry if this is too OT.