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PERIODIC MAINTENANCE AND MINOR REPAIR
6-25
6
NOTE:Using 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.CAUTION:
ECA10570
Improper drive chain slack will over-
load the engine as well as other vital
parts of the motorcycle and can lead
to chain slippage or breakage. To
prevent this from occurring, keep
the drive chain slack within thespecified limits.3. Tighten the locknuts, and then
tighten the axle nut to the specified
torque.
EAU34311
To adjust the drive chain slack
(XT660X)
1. Loosen the axle nut and the lock-
nut on each side of the swingarm.
2. To tighten the drive chain, turn the
adjusting bolt on each side of the
swingarm in direction (a). To loos-
en the drive chain, turn the adjust-
ing bolt on each side of the
swingarm in direction (b), and then
push the rear wheel forward.NOTE:Using the alignment marks on each
side of the swingarm, make sure that
both chain pullers are in the same posi-tion for proper wheel alignment.
CAUTION:
ECA10570
Improper drive chain slack will over-
load the engine as well as other vital
parts of the motorcycle and can lead
to chain slippage or breakage. To
prevent this from occurring, keep
the drive chain slack within thespecified limits.
3. Tighten the locknuts, then the axle
nut to their specified torques.
1. Axle nut
2. Drive chain slack adjusting nut
3. Locknut
4. Alignment marks
Tightening torque:
Locknut:
16 Nm (1.6 m·kgf, 11 ft·lbf)
Axle nut:
104 Nm (10.4 m·kgf, 75 ft·lbf)
1. Axle nut
2. Drive chain slack adjusting bolt
3. Locknut
4. Alignment marks
4
3
12(a)
(b)
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PERIODIC MAINTENANCE AND MINOR REPAIR
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6
EAU23271
Checking the front fork The condition and operation of the front
fork must be checked as follows at the
intervals specified in the periodic main-
tenance and lubrication chart.
To check the condition
WARNING
EWA10750
Securely support the vehicle so thatthere is no danger of it falling over.
Check the inner tubes for scratches,
damage and excessive oil leakage.
To check the operation
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.
2. While applying the front brake,
push down hard on the handlebars
several times to check if the front
fork compresses and rebounds
smoothly.
CAUTION:
ECA10590
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-pair it.
EAU23280
Checking the steering Worn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the pe-
riodic maintenance and lubrication
chart.
1. Place a stand under the engine to
raise the front wheel off the
ground.
WARNING
EWA10750
Securely support the vehicle so thatthere is no danger of it falling over.
2. Hold the lower ends of the front
fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the steering.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-30
6
EAU23290
Checking the wheel bearings The front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer check
the wheel bearings.
EAUM1730
Battery This model is equipped with a sealed-
type (MF) battery, which does not re-
quire any maintenance. There is no
need to check the electrolyte or to add
distilled water.CAUTION:
ECA10620
Never attempt to remove the battery
cell seals, as this would permanent-ly damage the battery.
To access the battery
1. Remove the seat. (See page
3-12.)
2. Remove the battery cover by re-
moving the bolts.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-35
6
EAUM1820
Replacing an auxiliary light
bulb If the auxiliary light bulb burns out, re-
place it as follows.
1. Remove cowling A together with
the headlight unit. (See page 6-5.)
2. Remove the auxiliary light socket
(together with the bulb) by pulling it
out.
3. Remove the defective bulb by pull-
ing it out.
4. Insert a new bulb into the socket.
5. Install the auxiliary light socket (to-
gether with the bulb) by pushing it
in.
6. Install the cowling together with
the headlight unit.
EAU24350
Supporting the motorcycle Since this model is not equipped with a
centerstand, follow these precautions
when removing the front and rear
wheel or performing other maintenance
requiring the motorcycle to stand up-
right. Check that the motorcycle is in a
stable and level position before starting
any maintenance. A strong wooden
box can be placed under the engine for
added stability.
To service the front wheel
1. Stabilize the rear of the motorcycle
by using a motorcycle stand or, if
an additional motorcycle stand is
not available, by placing a jack un-
der the frame in front of the rear
wheel.
2. Raise the front wheel off the
ground by using a motorcycle
stand.
To service the rear wheel
Raise the rear wheel off the ground by
using a motorcycle stand or, if a motor-
cycle stand is not available, by placinga jack either under each side of the
frame in front of the rear wheel or under
each side of the swingarm.
1. Auxiliary light bulb socket
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PERIODIC MAINTENANCE AND MINOR REPAIR
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6
EAU24360
Front wheel
EAUM1761
To remove the front wheel
WARNING
EWA10820
It is advisable to have a Yamaha
dealer service the wheel.
Securely support the motor-
cycle so that there is no dangerof it falling over.
1. Loosen the front wheel axle pinch
bolts, then the wheel axle and the
brake caliper bolts.
XT660RXT660X
2. Lift the front wheel off the ground
according to the procedure on
page 6-35.
3. Remove the brake caliper by re-
moving the bolts.
CAUTION:
ECA11070
Do not apply the brake after the
wheel has been removed together
with the brake disc, otherwise thebrake pads will be forced shut.
4. Pull the wheel axle out, and then
remove the wheel.
EAUM1811
To install the front wheel
1. Lift the wheel up between the fork
legs.
2. Insert the wheel axle.
3. Lower the front wheel so that it is
on the ground.
1. Wheel axle
2. Front wheel axle pinch bolt A
3. Front wheel axle pinch bolt B
1. Wheel axle
2. Front wheel axle pinch bolt A
3. Front wheel axle pinch bolt B
1. Bolt
2. Brake caliper
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-37
6 4. Install the brake caliper by install-
ing the bolts.
NOTE:Make sure that there is enough space
between the brake pads before install-
ing the brake caliper onto the brakedisc.
5. Tighten the wheel axle to the spec-
ified torque.
6. Tighten the wheel axle pinch bolt A
and pinch bolt B to the specified
torques.
7. Retighten the wheel axle pinch bolt
A to the specified torque.
8. Tighten the brake caliper bolts to
the specified torques.
9. Push down hard on the handlebar
several times to check for proper
fork operation.
EAU25080
Rear wheel
EAUM1773
To remove the rear wheel
WARNING
EWA10820
It is advisable to have a Yamaha
dealer service the wheel.
Securely support the motor-
cycle so that there is no dangerof it falling over.
1. Remove the drive chain guard by
removing the bolts.
XT660RXT660X
2. Loosen the axle nut.
XT660R
Tightening torques:
Wheel axle:
59 Nm (5.9 m·kgf, 43 ft·lbf)
Front wheel axle pinch bolt:
18 Nm (1.8 m·kgf, 13 ft·lbf)
Brake caliper bolt:
40 Nm (4.0 m·kgf, 29 ft·lbf)
1. Bolt
2. Drive chain guard
1. Bolt
2. Drive chain guard
1. Axle nut
2. Drive chain slack adjusting nut
3. Locknut
4. Brake caliper bracket
5. Brake caliper
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-38
6XT660X
3. Lift the rear wheel off the ground
according to the procedure on
page 6-35.
4. Loosen the locknut on each side of
the swingarm.
5. Turn the drive chain slack adjust-
ing nuts (or bolts according to the
model) fully in direction (a).
6. Remove the wheel axle by remov-
ing the axle nut.
7. Push the wheel forward, and then
remove the drive chain from the
rear sprocket.
NOTE:The drive chain cannot be disassem-bled.
8. Pull the wheel backward and move
the brake caliper away from the
wheel.CAUTION:
ECA11070
Do not apply the brake after the
wheel has been removed together
with the brake disc, otherwise thebrake pads will be forced shut.
EAUM2140
To install the rear wheel
1. Install the drive chain onto the rear
sprocket.
2. Install the wheel, the washer(s)
and the brake caliper bracket by
inserting the wheel axle from the
left-hand side.NOTE:
XT660R: Install the washer with
the “N” mark on the right-hand side
and the washer with the “O” mark
on the left-hand side. Be sure to in-
stall both washers with their marks
facing outward.
1. Axle nut
2. Drive chain slack adjusting bolt
3. Locknut
4. Brake caliper bracket
5. Brake caliper
3
1245(a)
1. Brake caliper
2. Brake disc
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PERIODIC MAINTENANCE AND MINOR REPAIR
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6
XT660X: Install the washer on the
right-hand side.
Make sure that the retainer on the
swingarm is inserted into the slot in
the brake caliper bracket.
Make sure that there is enough
space between the brake pads be-fore installing the wheel.
3. Lower the rear wheel so that it is
on the ground.
4. Adjust the drive chain slack. (See
page 6-24.)
5. Tighten the axle nut to the speci-
fied torque.6. Install the drive chain guard by in-
stalling the bolts.
EAU25870
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.
1. Retainer
2. Slot
Tightening torque:
Locknut:
16 Nm (1.6 m·kgf, 11 ft·lbf)
Axle nut:
104 Nm (10.4 m·kgf, 75 ft·lbf)
U5VKE1E0.book Page 39 Tuesday, July 18, 2006 1:00 PM