Hellow to all in this forum, im here to help anyone with a problem or anything else. Here's my story, my first motorbike was a 26" and the engine was a stock engine with a 39th sproket, i broke the connecting rod when i was on a race. Then i started building another, the cylinder is ported , not polished, i make the cylinder head high compression and some work to the piston, it has the stock carburator ported and the intake manifold ported, i dont have expansion chamber , i have a open pipe, its on a 26" with a 32th sproket and it gets up to 48mph, i hope to buy a expansion chamber and a 17.5 to 21mm carb so it can go un to 54mph or more. One friend have the same combination as me but he have a 17.5mm dellorto carb with a 28th sproket on a 26" bicycle he makes 58mph. And he isnt the fastest one, the fastest one is a 20" bicycle that haves all things that we can do and a 24th sproket and it goes up to 63mph. Thats all ,,hope you like this post
