Yamaha YFM80GV, Owner'S Manual

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EBU00296
Carburetor adjustment
The carburetor is a vital part of the engine and
requires very sophisticated adjustment. Most
adjusting should be left to a Yamaha dealer who
has the professional knowledge and experience
to do so. However, the idling speed may be per-
formed by the owner as a part of the usual main-
tenance routine.
c C
The carburetor was set at the Yamaha facto-
ry after many tests. If the settings are dis-
turbed by someone without sufficient techni-
cal knowledge, poor engine performance and
damage may result.
EBU13020
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 engine to 4,000
to 5,000 r/min. The engine is warm when it
quickly responds to the throttle.
2. Connect the tachometer to the spark plug
lead, and then set the idle to the specified
idling speed by adjusting the throttle stop
screw. Turn the screw in direction
a
to
increase the engine speed, and in direction
b
to decrease the engine speed.
Specified idle speed:
1,800 r/min
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