The 01 scrambler 90 won't run it will idle but it does not rev up and when it does it back fires, and eventually dies sounds like a carb problem but cleaned it several times and does not help, thought it was the crankshaft seals but not the case either, checked the reeds also look OK.
Any suggestions!!!!
At one point the exhaust was plugged up with carbon cut it apart and cleaned it out welded back together but has run good since then. How important is the exhaust and backpressure on these atvs.