PERIODIC MAINTENANCE AND ADJUSTMENT
7-15
7
EAU21280
Adjusting the carburetor
The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
carburetor adjustments should be left
to a Yamaha dealer, who has the nec-
essary professional knowledge and
experience. The adjustment described
in the following section, however, may
be serviced by the owner as part of
routine maintenance.
ECA10550
NOTICE
_
The carburetor has been set and
extensively tested at the Yamaha
factory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine.
_
EAUU0320
Adjusting the engine idling
speed
The engine idling speed must be
checked and, if necessary, adjusted
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart.
The engine should be warm before
making this adjustment.
TIP
_
●
The engine is warm when it quick-
ly responds to the throttle.
●
A diagnostic tachometer is need-
ed to make this adjustment.
_
1. Open the seat. (See page 4-8 for
seat opening and closing proce-
dures.)
2. Remove panel A. (See page 7-7
for panel removal and installation
procedures.)
3. Attach the tachometer to the
spark plug lead.
4. Check the engine idling speed
and, if necessary, adjust it to
specification as follows.
5. Remove the rubber cap and in-
sert a Phillips screwdriver into the
throttle stop screw hole.
6. To increase the engine idling
speed, turn the screw in direction
(a). To decrease the engine idling
speed, turn the screw in direction
(b).
1. Rubber cap
ZAUU0075
E_4C9E1.book Page 15 Thursday, January 15, 2009 3:03 PM