Ok finally I get the idea about some parts are interchangeable so I got this(I think) Frankenbike running.rode it around a bit seems slow to get moving etc.my friend reciently got a sit on scooter that seems to have ample power.btw engines seem to appear the same. I'm hoping his has more HP but incase where and what should I check to make sure this stitched together bike I got is running 100%? Carb ? Already replaced clutch.gearbox? Gas fuel mix ?i measured the piston to be about 1.5 inch(38.1mm) if not a little over well enough typing any ideas and I'll will look more here on the forums thanks pocket bike gang !