Thumpstar ATV 125CC, Owner'S Manual

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98 ATV 250 - Periodic Maintenance and Adjustments
ADJUSTING THE CARBURETOR
The carburetor should be checked and, if necessary, adjusted at the in-
tervals specified in the periodic maintenance and lubrication chart. The
carburetor is an important part of the engine and requires very sophisticat-
ed adjustment. Therefore, most carburetor adjustments should be left to a
dealer, who has the necessary professional knowledge and experience. The
adjustment described in the following section, however, may be performed
by the owner as part of routine maintenance.
NOTE:
The carburetor has been set and extensively tested at the factory. Changing
these settings without sufficient technical knowledge may result in poor
performance of or damage to the engine.
ADJUSTING THE ENGINE IDLING SPEED
The engine idling speed must be checked and, if necessary, adjusted as fol-
lows at the intervals specified in the periodic maintenance and lubrication
chart.
NOTE:
A diagnostic tachometer is needed to make this adjustment.
1. Start the engine and warm it up.
NOTE:
A diagnostic tachometer is needed to make this adjustment. The engine is
warm when it quickly responds to the throttle.
2. Attach the tachometer to the spark plug lead.
3. Check the engine idling speed and, if necessary, adjust it to specification
by turning the throttle stop screw at the carburetor. To increase the engine
idling speed, turn the throttle stop screw clockwise, and to decrease it, turn
the screw counter-clockwise.