My 66cc motor won't hardly run with the stock muffler, when I take it off it runs like a champ. Anyone have bikeberrys expansion chamber with muffler? What do yo think of it? How much louder is a regular expansion chamber?
Just stuff the small cylinder Briggs muffler in the end.
(I've ran a multitude of exhaust systems and this one has the best low torque and high speed power that I've found.)