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 lubrication
chart.
TIP
A diagnostic tachometer is needed to
make this adjustment.
1. Attach the tachometer to the spark
plug lead.
2. Start the engine and warm it up for
several minutes at 1000–2000
r/min while occasionally revving it
to 4000–5000 r/min.
TIP
The engine is warm when it quickly re-
sponds to the throttle.
3. Check the engine idling speed
and, if necessary, adjust it to spec-
ification by turning the throttle stop
screw. To increase the engine
idling speed, turn the screw in di-
PERIODIC MAINTENANCE AND ADJUSTMENT
EAU21362
rection (a). To decrease the en-
gine idling speed, turn the screw in
direction (b).
(b)
1
1. Throttle stop screw
Engine idling speed:
1600–1800 r/min
TIP
If the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment.
Adjusting the throttle cable
free play
(a)
1. Throttle cable free play
The throttle cable free play should mea-
sure 3.0–5.0 mm (0.12–0.20 in) at the
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, adjust it as follows.
TIP
The engine idling speed must be cor-
rectly adjusted before checking and ad-
justing the throttle cable free play.
1. Loosen the locknut.
7-11
EAU21370
7