2004 Official factory service manual for Yamaha YFZ450S ATV Quad., Page 82Get this manual
ADJUSTING THE ENGINE IDLING SPEED ADJUSTING THE THROTTLE LEVER FREE PLAY a b
6Adjust: engine idling speed
aTurn the throttle stop screw in direction or until the specified idling speed is obtainedDirection Direction Idling speed becomes higherIdling speed becomes lower
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