Periodic maintenance and adjustment
7-12
7
EAU42111
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 ex-
perience. The adjustment described in
the following section, however, may be
serviced by the owner as part of rou-
tine maintenance.
ECA10551
The carburetor has been set and ex-
tensively tested at the Yamaha fac-
tory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine.
EAU44391
Adjusting the engine idling
speed
The engine idling speed must be ad-
justed when necessary.
1. Start the engine and thoroughly
warm it up.
2. Turn the throttle stop screw until
the engine runs at the lowest pos-
sible speed.
3. To increase the engine idling
speed, turn the throttle stop screw
in direction (a). To decrease the
engine idling speed, turn the throt-
tle stop screw in direction (b).
1. Throttle stop screw
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