2007-2009 Honda TRX300EX TRX300X service manual, Page 352Get this manual
TROUBLESHOOTING 7Cylinder Compression Inspection
Test cylinder compressionIs the compression low?
Valve clearance too small Valve stuck open Worn cylinder and piston rings Damaged cyl inder head gasket Seized valve Improper valve timing
- GO TO STEP 8
8Carburetor Inspection
Check carburetor for clogging Is the carburetor clogged?
YESCarburetor not serviced frequently enough
- GO TO STEP 9
9Spark Plug Inspection
Remove and inspect spark plug Is the spark plug fouled or discolored?