where do you live?
If you know anyone in the island of Bermuda, that's the place to get stuff for those bikes. The guys down there take those things and make em do a clean 70 mph! With a bigger header pipe, take some plates out of the exhaust and she'll sound pretty rude too. Like I said, Bermuda is the place to get parts for that thing. One of my friends has a shop and he sells like every part you could want for em. From reed cages, manifolds, carbs, bigger blocks, matching machined head, i mean EVERYTHING even plastics. The shop is called Cycle Care if you want to try and reach them by e-mail.