I was thinking of a chain drive on the outside of the engine for affect. I think it would work better to use a Honda CF130 top end. And one advantage is that the Chinese have a copy of that engine and a unlimited supply of parts. they are OHC and I could use more of the parts, I have one but it is in a bike, I will look for parts to one out there, I know I have a cylinder but I cant remember if I have a head. Its just an idea. I would like to see if we could have them made, if I can pull it off, Quinton do you have a connection for manufacture? Have fun, Dave
PS: I went out to see if I could find the parts and found another engine, in, another bike, I put one in a CT90 bike years ago. I did find a XR70 engine and a pile of CT90 engines and a CM91 engine, all 90cc. Too many 50cc engines to count, I need a happy time 4 stroke