I know about OHV conversion, but Im talking like taking a 20-50's motorcycle head off like a harley or indian and retrofitting it on the whizzer. I've been looking at a lot of the cylinders from those motorcycles and they have the same basic design especially the harley flatheads of the 30s and 40s and an early harley sportster KH. The whizzer piston is significantly smaller by 19mm or about 1/2 in, also looking at a matchless cylinder and head seems to be about the same design. I know it seems far fetched but there have been parts retrofitted before on engines. One thing I am thinking about is the bolt pattern. Most likely some type of adaptor would have to be made. The only real concern I have is how the valves would match up and how i would make that work. I have an idea on that part. And also the connecting rod, how that would match up or maybe i would have to find a rod that would fit the crank and the length of the cylinder. Another issue would be the amount of oil needed since its a bigger cylinder and piston so the oil breather would need to be taller to support more oil. If the OHV conversion can be done i think a retrofit cylinder could be done. I just have to find the right now. Thats why i was wondering if anyone knows someone that has done this so maybe I can have some knowledge on what was uses.
Does anyone have a whizzer crankcase with the head off that could take some measurements of the opening and post some pictures.