rebuilt all engine had it runnin runnin it in went to start it this mornin havin none of it brand new plug piston n rings good spark fuel comin threw just keeps backfiring

chris moule, April 2010

ok well its either fouled the spark plug with dirty burnt 2 stroke oil or the compression is low and the backfiring is the unburnt fuel vapour burning in the exhaust,its common on a 2 stroke to make this noise its usually a chuffing sound from the exhaust and usually 125 cc bikes thet do it though.

adam bike doctor, April 2010