2005-2011 Honda FourTrax Foreman TRX500 FE/FPE/FM/FPM/TM Service Manual, Page 88Get this manual
MAINTENANCE
AIR CLEANER HOUSING DRAIN HOSE
Remove the drain hose from the bottom of the air cleaner housing to empty any deposits
Install the drain hose securely
SPARK PLUG
Remove the resonator chamber and turn over the rubber seal (page 4-7)Disconnect the spark plug cap and clea around the spark plug baseNOTE
Clean around the spark plug base with compressed air before removing the plug, and be sure that no debris is allowed to enter the combustion chamber
Remove the spark plug
Check the insulator for cracks or damage, and the electrodes for wear, fouling or discolorationReplace the plug if necessaryRECOMMENDED SPARK PLUG: BKR5E-11 (NGK), K16PR-U11 (DENSO)