Yamaha BEARTRACKER YFM250XN, Owner'S Manual

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EBU00296
Carburetor adjustment
The carburetor is a vital part of the engine
and requires very sophisticated adjust-
ment. Most adjusting should be left to a
Yamaha dealer who has the professional
knowledge and experience to do so. How-
ever, the idling speed may be performed
by the owner as a part of the usual mainte-
nance routine.
CAUTION:
The carburetor was set at the Yamaha fac-
tory after many tests. If the settings are
disturbed by someone without sufficient
technical knowledge, poor engine perfor-
mance and damage may result.
EBU00301
Idle speed adjustment
NOTE:
A diagnostic tachometer must be used for
this procedure.
1. Start the engine and warm it up for a
few minutes at approximately 1,000 to
2,000 r/min. Occasionally rev the en-
gine to 4,000 to 5,000 r/min. The en-
gine is warm when it quickly responds
to the throttle.
2. Connect the tachometer and set the
idle to the specified idling speed by
adjusting the throttle stop screw. Turn
the screw in to increase engine speed,
and out to decrease engine speed.
Specified idle speed:
1,400 ~ 1,500 r/min