Why Does a Motorcycle Emit Smoke?

[McAlessandra]

Motorcycle smoke emission may be due to spark plug issues. Black smoke from exhaust: Possible causes include a clogged air filter, blocked compensation air passage or idle air passage in the carburetor, excessively high float chamber fuel level allowing unatomized fuel to enter the cylinder causing incomplete combustion, severe wear of the main jet increasing fuel injection volume leading to incomplete combustion, or the starting heating automatic valve remaining in the open position even after engine warm-up, preventing automatic closure and resulting in an overly rich mixture. Spark plug malfunction: If the spark plug misfires or has weak sparks, carbon deposits should be removed or the plug replaced. If a motorcycle frequently burns out spark plugs without regular intervals, it indicates an overly rich air-fuel mixture ratio in the combustion chamber. This means excessive fuel with insufficient air intake, which over time will repeatedly flood the spark plugs. Frequent spark plug replacement should not be considered a permanent solution.