The project is an off road bike. It's bigger than a mini bike but a little different than a dirt bike.
I do have room for liquid cooled but I would also consider air cooled. I would like an engine with a transmission attached. That's good to know about the belt drive automatics though.
I wouldn't mind having a hayabusa motor, but I don't want to spend too much on it. That would be awsome if I could pick one up for cheep somewhere.
Any suggestions on where to look for a decent used engine?