The engine start easily.have idling.i give gas when the cracking the exhaust and drowning.the valve clearence is good ignition good but i need the carburator full description.thanks!
Back firing through the exhaust is mostly caused by a too lean condition. If the bike has not been run for awhile with gas left in the carburetor the problem may be a completely or partially clogged pilot or main jet. Just remove the float bowl and the pilot and main jet will be right there. Use a welding torch tip cleaner to "poke through" the hardened fuel. remove the jets before cleaning.