need help in getting more top end speed
hi i have a 80cc, yeah i know 69cc, motor , i have moded the exhust byb putting on an expansion chamber, runs very well , awesome power , goes up any hill no prob no peddling, but around 35kmph it seems to lack power and kind of wants to stall its self at around that speed. with the stock muffler i could get to faster speeds but less power.
i was wondering if it might be a carb isue, do i need a bigger one??/ or do i need a larger jet hole to get more fuel in there???
can anyone help.....