2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 479Get this manual
IGNITION SYSTEM (After '05) OPERATION INSPECTION If the engine does not start, check for the followingRemove the throttle housing cover (page 17-9)Remove the throttle drum cover (page 8-7)Operate the throttle lever and check for smooth operation of the throttle drum in all steering positionIf the throttle drum operation is not smooth, lubricate or replace the throttle cableCheck the throttle lever free play (page 4-6)THROTTLE CABLE THROTTLE LEVER SWITCH
The ICM will cut-off the ignition when the throttle lever free play is adjusted to less than mm (732 in)If the engine does not start, check the throttle lever free play and readjust it
If the throttle drum operation is normal and the engine still does not start, check the throttle lever switch and carburetor switch (page 22-13)
THROTTLE DRUM