2004 Official factory service manual for Yamaha YFZ450S ATV Quad., Page 315Get this manual
IGNITION SYSTEM
CHECKING THE THROTTLE OVERRIDE SYSTEM WARNING Make sure that the parking brake is applied Make sure that the transmission is in neutralNOTE: Make sure that the throttle lever moves smoothly1 Remove: throttle lever cover throttle position sensor carburetor switchthrottle stop screw assembly cover Refer to "CARBURETOR" in chapter 6
2Start the engine3Check: throttle switch 1
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