2008 YAMAHA XT660X maintenance

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
U5VKE1E0.book Page 37 Tuesday, July 18, 2006 1:00 PM

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
U5VKE1E0.book Page 38 Tuesday, July 18, 2006 1:00 PM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-39
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

PERIODIC MAINTENANCE AND MINOR REPAIR
6-40
6
EAU25921
Troubleshooting charts Starting problems or poor engine performance
WARNING
EWA10840
Keep away open flames and do not smoke while checking or working on the fuel system.
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
U5VKE1E0.book Page 40 Tuesday, July 18, 2006 1:00 PM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-41
6 Engine overheating
WARNING
EWA10400


Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.


After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the hissingsound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.
NOTE:If coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended coolantas soon as possible.
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See NOTE.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
U5VKE1E0.book Page 41 Tuesday, July 18, 2006 1:00 PM

INDEX
AAir filter element and check hose,
replacing and cleaning ....................... 6-16
Anti-theft alarm (optional) ....................... 3-7
Auxiliary light bulb, replacing ................ 6-35BBattery .................................................. 6-30
Brake and clutch levers, checking and
lubricating ........................................... 6-27
Brake fluid level, checking .................... 6-23
Brake lever ............................................. 3-9
Brake pedal .......................................... 3-10
Brake pedal, lubricating ........................ 6-28CCables, checking and lubricating .......... 6-27
Care ........................................................ 7-1
Catalytic converter ................................ 3-12
Clutch lever............................................. 3-9
Clutch lever free play, adjusting ........... 6-21
Coolant ................................................. 6-13
Coolant temperature warning light.......... 3-4
Cowlings and panels, removing and
installing ............................................... 6-5DDimmer switch ........................................ 3-8
Drive chain, cleaning and lubricating .... 6-26
Drive chain slack .................................. 6-24EEngine break-in ...................................... 5-3
Engine idling speed .............................. 6-17
Engine oil and oil filter element............. 6-10
Engine stop switch.................................. 3-8
Engine trouble warning light ................... 3-4
FFront and rear brake pads, checking .... 6-22
Front fork, checking...............................6-29
Fuel ....................................................... 3-11
Fuel consumption, tips for reducing ........ 5-3
Fuel level warning light............................ 3-4
Fuel tank cap......................................... 3-10
Fuses, replacing .................................... 6-32HHandlebar switches ................................. 3-7
Hazard switch.......................................... 3-8
Headlight bulb, replacing....................... 6-33
High beam indicator light......................... 3-4
Horn switch ............................................. 3-8IIdentification numbers ............................. 9-1
Ignition circuit cut-off system ................. 3-15
Immobilizer system .................................3-1
Immobilizer system indicator light ........... 3-4
Indicator and warning lights .................... 3-3KKey identification number ........................ 9-1MMain switch/steering lock ........................ 3-2
Model label .............................................. 9-2
Multi-function display...............................3-5NNeutral indicator light .............................. 3-3PParking ....................................................5-4
Part locations .......................................... 2-1
Pass switch ............................................. 3-8
Periodic maintenance and lubrication
chart ......................................................6-2Pre-operation check list .......................... 4-2
RRear brake light switch, adjusting ......... 6-22SSafety information ................................... 1-1
Seat ...................................................... 3-12
Shifting .................................................... 5-2
Shift pedal ............................................... 3-9
Shock absorber assembly, adjusting .... 3-13
Sidestand .............................................. 3-14
Sidestand, checking and lubricating ..... 6-28
Spark plug, checking .............................. 6-9
Specifications.......................................... 8-1
Starting the engine.................................. 5-1
Start switch ............................................. 3-8
Steering, checking ................................ 6-29
Storage ................................................... 7-3
Storage compartment ........................... 3-13
Supporting the motorcycle .................... 6-35TThrottle cable free play, checking ......... 6-18
Throttle grip and cable, checking and
lubricating ........................................... 6-27
Tires ...................................................... 6-18
Tool kit .................................................... 6-1
Troubleshooting .................................... 6-39
Troubleshooting charts ......................... 6-40
Turn signal indicator light ........................ 3-3
Turn signal light bulb or tail/brake light
bulb, replacing .................................... 6-34
Turn signal switch ................................... 3-8VVehicle identification number .................. 9-1
U5VKE1E0.book Page 1 Tuesday, July 18, 2006 1:00 PM