Page 58 of 86
PERIODIC MAINTENANCE AND ADJUSTMENT
6-22
6
EAU22760
Drive chain slack The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22773
To check the drive chain slack
1. Place the motorcycle on the side-
stand.TIPWhen checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.2. Shift the transmission into the neu-
tral position.
3. Move the rear wheel by pushing
the motorcycle to locate the tight-
est portion of the drive chain, and
then measure the drive chain slack
as shown.4. If the drive chain slack is incorrect,
adjust it as follows.
EAU22934
To adjust the drive chain slack
1. Loosen the axle nut, then loosen
the locknut at each end of the
swingarm.
2. To tighten the drive chain, turn the
drive chain slack adjusting nut at
each end of the swingarm in direc-
tion (a). To loosen the drive chain,
turn the adjusting nut at each end
of the swingarm in direction (b),
and then push the rear wheel for-
ward. NOTICE: Improper drive
chain slack will overload the en-
gine as well as other vital partsof the motorcycle and can lead
to chain slippage or breakage.
To prevent this from occurring,
keep the drive chain slack with-
in the specified limits.
[ECA10571]
TIPUsing the alignment marks on each
side of the swingarm, make sure that
both adjusting nuts are in the same po-
sition for proper wheel alignment.3. Tighten the locknuts, and then
tighten the axle nut to the specified
torques.
Drive chain slack:
40.0–50.0 mm (1.57–1.97 in)
1. Drive chain slack
1. Axle nut
2. Drive chain slack adjusting nut
3. Locknut
4. Alignment marks
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Page 70 of 86
PERIODIC MAINTENANCE AND ADJUSTMENT
6-34
6
EAUM2640
To install the front wheel
1. Lift the wheel up between the fork
legs.
2. Install the speed sensor at the
wheel hub.TIPMake sure that the projections on the
speed sensor rotor are aligned with the
notches in the wheel hub and that the
slot in the speed sensor fits over the re-
tainer on the fork leg.3. Insert the wheel axle.
4. Lower the front wheel so that it is
on the ground.5. Push down hard on the handlebar
several times to check for proper
fork operation.
6. Install the brake caliper by install-
ing the bolts.
TIPMake sure that there is enough space
between the brake pads before install-
ing the brake caliper onto the brake
disc.7. Install the speed sensor lead hold-
er by installing the screw
(WR125R only).
8. Tighten the wheel axle, front wheel
axle pinch bolts and brake caliper
bolts to their specified torques.
EAU25080
Rear wheel
EAUM2661
To remove the rear wheel
WARNING
EWA10821
To avoid injury, securely support the
vehicle so there is no danger of it
falling over.1. Loosen the locknut and drive chain
slack adjusting nut on each side of
the swingarm.
2. Loosen the axle nut.
1. Speed sensor
Tightening torques:
Wheel axle:
58 Nm (5.8 m·kgf, 42 ft·lbf)
Front wheel axle pinch bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Brake caliper bolt:
30 Nm (3.0 m·kgf, 22 ft·lbf)
1. Axle nut
2. Drive chain slack adjusting nut
3. Locknut
U22BE1E0.book Page 34 Wednesday, September 16, 2009 1:46 PM
Page 72 of 86
PERIODIC MAINTENANCE AND ADJUSTMENT
6-36
63. Install the axle nut.
4. Lower the rear wheel so that it is
on the ground.
5. Adjust the drive chain slack. (See
page 6-22.)
6. Tighten the axle nut to the speci-
fied torque.
EAU25871
Troubleshooting Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur dur-
ing operation. Any problem in the fuel,
compression, or ignition systems, for
example, can cause poor starting and
loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look like
Yamaha parts, but they are often inferi-
or, have a shorter service life and can
lead to expensive repair bills.
WARNING
EWA15141
When checking the fuel system, do
not smoke, and make sure there are
no open flames or sparks in the ar-
ea, including pilot lights from waterheaters or furnaces. Gasoline or
gasoline vapors can ignite or ex-
plode, causing severe injury or
property damage.
Tightening torque:
Axle nut:
90 Nm (9.0 m·kgf, 65 ft·lbf)
U22BE1E0.book Page 36 Wednesday, September 16, 2009 1:46 PM