Perio
d
ic maintenance an
d
a
d
justment
7-14
7
EAU21363
A
d
justin
g
the en
g
ine i
d
lin
g
spee
d
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
specification by turning the throt-
tle stop screw. To increase the en-
gine idling speed, turn the screw in
direction (a). To decrease the en-
gine idling speed, turn the screw in
direction (b).
TIP
If the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment.
EAU21377
A
d
justin
g
the throttle
g
rip free
play
Measure the throttle grip free play as
shown.
Periodically check the throttle grip free
play and, if necessary, adjust it as fol-
lows.
TIP
The engine idling speed must be cor-
rectly adjusted before checking and
adjusting the throttle grip free play.
1. Loosen the locknut.
1. Throttle stop screw
En
g
ine i
d
lin
g
spee
d
:
1300–1500 r/min
1. Throttle grip free play
Throttle
g
rip free play:
3.0–5.0 mm (0.12–0.20 in)
UBSR81E0.book Page 14 Monday, April 3, 2023 10:39 AM
