If white smoke is coming out of your bike's exhaust when you rev the engine while stationary, it could indicate a potential issue with the engine. Here are a few possible causes for white smoke:
Condensation: When the engine is cold, it's normal to see some white smoke at startup, which is usually caused by condensation in the exhaust system. This should dissipate quickly and is generally not a cause for concern.
Coolant leak: White smoke that persists or increases with engine revs could be a sign of a coolant leak. If coolant is entering the combustion chamber, it can cause white smoke to come out of the exhaust. Check your coolant levels regularly and inspect for any signs of leaks or a sweet smell in the exhaust.
Engine oil leak: If the engine is burning oil, it can produce white smoke. This could indicate a problem with the piston rings, valve seals, or other components that prevent oil from entering the combustion chamber. Check the oil level regularly and look for any signs of oil leaks.
Head gasket failure: A damaged or blown head gasket can cause coolant to mix with the combustion chamber, resulting in white smoke. This issue may also be accompanied by other symptoms such as overheating, loss of coolant, or oil contamination.
It's important to have your bike inspected by a qualified mechanic to diagnose and address the specific cause of the white smoke. They can perform a thorough examination of the engine and its components to determine the source of the issue and recommend the necessary repairs.