6
6-10
PERIODIC MAINTENANCE AND MINOR REPAIR
Carburetor adjustment
The carburetor is an importance part of
the engine which requires a very fine
adjustment. Therefore, the carburetor
adjustment should be carry out with the
expertise and experience of a Yamaha
dealer. However, as described in the next
section, the owners can perform the
following as specified in the periodic
maintenance and minor repair.
NOTICE
The carburetor has been designed and
extensively tested at Yamaha factory.
Changing these settings without
sufficient technical knowledge may
result in engine performance
degradation or damage to the engine.
Adjusting the engine idling speed
The engine idling speed must be
checked and, if necessary, adjusted as
per the intervals specified in the
periodic maintenance and lubrication
chart.
The engine should be warm up before
making this adjustment.
TIP
When the engine is warm it will quickly
responds to the throttle. A diagnostic
tachometer is needed to make this
adjustment.
Remove cowling. (See page 6-5.)
Attach the diagnostic tachometer to
the spark plug lead. Check the
engine idling speed and, if
necessary, adjust it to specification
by turning the idling adjust screw. To
increase the engine idling speed,
turn the screw to the right. To
decrease the engine idling speed,
turn the screw to the left.
1.
2.
Engine idling speed:
1400–1600 r/min
TIP
If the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment.
3. Install the cowling.
