problem with expansion chamber
hi i have a stock 67cc motor and i have put on a moded expansion chamber, the pipe to the chamber is 12inch long and then i have atatched the stock muffler end onto the expansion chamber.
the bike now runs very torqie at low speed but at mid top too top end it want to slow down and seems like it is starving of either fuel or air.
it also seems to really over rev and is louder then expected at top speed. i dont run it long at top speed i pull in the clutch and roll where possible
an anyone help with any of this and to also get it quieter.??????/