2001-2006 Honda TRX 300EX Sportrax 300EX Factory Service Manual, Page 107Get this manual
CYLINDER HEADVALVES
TROUBLESHOOTING
Engine lop-end problems usually affect engine performanceThese can be diagnosed by com pression testor by tracking noise to he top-en dIf the performance is poor at low speeds, check for white smoke in the crankcase breather tubeIf the lube is smoky, check for seized piston ring (Section 81COMPRESSION TOO LOW, HARD STARTING OR POOR PERFORMANCE AT LOW SPEED Valves EXCESSIVE SMOKE
- Incorrect valve adjustmentBurned or bent valves -Incorrect valve timingBroken velve springUneven valve seat ingValve stuck open Cylinder headleaking or damaged cylinder heed gasketWarped or cracked cyli nder headLoose spark plug Faulty cylinder, piston (Section 81