2005-2006 Honda ATV TRX500FE/FM/TM FourTrax Foreman Factory Service Manual, Page 445Get this manual
TROUBLESHOOTING
POOR PERFORMANCE AT HIGH SPEED
1Fuel Flow Inspection Disconnect the fuel hose and check fuel flow to carburetorDoes fuel flow freely? NORestricted fuel hose Restricted fuel tank breather hose Faulty fuel valve Clogged fuel strainer YESGO TO STEP 22Carburetor Inspection Check the carburetor for cloggingAre the carburetor passages clear? NO YESCarburetor not serviced frequently enoughGO TO STEP 3
3Valve Timing Inspection Check the valve timingIs the valve timing correct? NO YESCamshaft not installed properlyTO STEP 4
4Ignition Timing Inspection Check the ignition timingIs the ignition timing as specified? NO YESFaulty engine control module (ECM) Faulty ignition pulse generatorGO TO STEP 55Valve Spring Inspection Check the valve springsIs the valve spring free length as specified? NOFaulty valve spring