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PERIODIC MAINTENANCE AND MINOR REPAIR
6-19
6
WARNING
EWA11020
Because loading has an enormous
impact on the handling, braking,
performance and safety characteris-
tics of your motorcycle, you should
keep the following precautions in
mind.
NEVER OVERLOAD THE
MOTORCYCLE! Operation of an
overloaded motorcycle may re-
sult in tire damage, loss of con-
trol, or severe injury. Make sure
that the total weight of rider,
passenger, cargo, and accesso-
ries does not exceed the speci-
fied maximum load for the
vehicle.
Do not carry along loosely
packed items, which can shift
during a ride.
Securely pack the heaviest
items close to the center of the
motorcycle and distribute the
weight evenly on both sides.
Adjust the suspension and tire
air pressure with regard to the
load.
Check the tire condition and airpressure before each ride.
Tire inspection
The tires must be checked before each
ride. If the center tread depth reaches
the specified limit, if the tire has a nail or
glass fragments in it, or if the sidewall is
cracked, have a Yamaha dealer re-
place the tire immediately.
Tire air pressure (measured on cold
tires):
0–90 kg (0–198 lb):
Front:
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
XT660X 210 kPa (30 psi) (2.10
kgf/cm²)
Rear:
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
XT660X 210 kPa (30 psi) (2.10
kgf/cm²)
90–186 kg (198–410 lb):
Front:
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
XT660X 220 kPa (32 psi) (2.20
kgf/cm²)
Rear:
XT660R 225 kPa (33 psi) (2.25
kgf/cm²)
XT660X 230 kPa (33 psi) (2.30
kgf/cm²)
Off-road riding:
Front:
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
Rear:
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
Maximum load*:
186 kg (410 lb)
* Total weight of rider, passenger, car-
go and accessories
1. Tire sidewall
2. Tire tread depth
Minimum tire tread depth (front and
rear):
1.6 mm (0.06 in)
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PERIODIC MAINTENANCE AND MINOR REPAIR
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6
NOTE:The tire tread depth limits may differ
from country to country. Always complywith the local regulations.
Tire information
This motorcycle is equipped with tube
tires.
WARNING
EWA10460
The front and rear tires should
be of the same make and de-
sign, otherwise the handling
characteristics of the vehicle
cannot be guaranteed.
After extensive tests, only the
tires listed below have been ap-
proved for this model byYamaha Motor Co., Ltd.
WARNING
EWA10570
Have a Yamaha dealer replace
excessively worn tires. Besides
being illegal, operating the
motorcycle with excessively
worn tires decreases riding sta-
bility and can lead to loss of
control.
The replacement of all wheel-
and brake-related parts, includ-
ing the tires, should be left to a
Yamaha dealer, who has the
necessary professional knowl-
edge and experience.
It is not recommended to patch
a punctured tube. If unavoid-
able, however, patch the tube
very carefully and replace it as
soon as possible with a high-quality product.
Front tire:
Size:
XT660R 90/90-21M/C 54S,
90/90-21M/C 54T
XT660X 120/70R17 M/C 58H,
120/70ZR17 M/C 58W,
120/70ZR17 M/C 58W
Manufacturer/model:
XT660R METZELER/TOURANCE
FRONT,
MICHELIN/SIRAC
XT660X PIRELLI/DRAGON,
METZELER/SPORTEC M1,
MICHELIN/RADIAL PILOT
SPORT
Rear tire:
Size:
XT660R 130/80-17M/C 65S,
130/80-17M/C 65T
XT660X 160/60R17 M/C 69H,
160/60ZR17 M/C 69W,
160/60ZR17 M/C 69W
Manufacturer/model:
XT660R METZELER/TOU-
RANCE,
MICHELIN/SIRAC
XT660X PIRELLI/DRAGON,
METZELER/SPORTEC M1,
MICHELIN/RADIAL PILOT
SPORT
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6
EAU21940
Spoke wheels To maximize the performance, durabil-
ity, and safe operation of your motor-
cycle, note the following points
regarding the specified wheels.
The wheel rims should be checked
for cracks, bends or warpage, and
the spokes for looseness or dam-
age before each ride. If any dam-
age is found, have a Yamaha
dealer replace the wheel. Do not
attempt even the smallest repair to
the wheel. A deformed or cracked
wheel must be replaced.
The wheel should be balanced
whenever either the tire or wheel
has been changed or replaced. An
unbalanced wheel can result in
poor performance, adverse han-
dling characteristics, and a short-
ened tire life.
Ride at moderate speeds after
changing a tire since the tire sur-
face must first be “broken in” for it
to develop its optimal characteris-
tics.
EAU22041
Adjusting the clutch lever free
play The clutch lever free play should mea-
sure 10.0–15.0 mm (0.39–0.59 in) as
shown. Periodically check the clutch le-
ver free play and, if necessary, adjust it
as follows.
1. Loosen the locknut at the clutch le-
ver.
2. To increase the clutch lever free
play, turn the adjusting bolt in di-
rection (a). To decrease the clutch
lever free play, turn the adjusting
bolt in direction (b).
NOTE:If the specified clutch lever free play
could be obtained as described above,
tighten the locknut and skip the rest of
the procedure, otherwise proceed asfollows.
3. Fully turn the adjusting bolt at the
clutch lever in direction (a) to loos-
en the clutch cable.
4. Loosen the locknut at the crank-
case.
1. Locknut
2. Clutch lever free play adjusting bolt
3. Clutch lever free play
1. Locknut
2. Clutch lever free play adjusting nut (crank-
case)
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PERIODIC MAINTENANCE AND MINOR REPAIR
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65. To increase the clutch lever free
play, turn the adjusting nut in direc-
tion (a). To decrease the clutch le-
ver free play, turn the adjusting nut
in direction (b).
6. Tighten the locknut at the clutch le-
ver and the crankcase.
EAU22270
Adjusting the rear brake light
switch The rear brake light switch, which is ac-
tivated by the brake pedal, is properly
adjusted when the brake light comes
on just before braking takes effect. If
necessary, adjust the brake light switch
as follows.
Turn the adjusting nut while holding the
rear brake light switch in place. To
make the brake light come on earlier,
turn the adjusting nut in direction (a). To
make the brake light come on later, turn
the adjusting nut in direction (b).
EAU22390
Checking the front and rear
brake pads The front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
EAU22430
Front brake pads
Each front brake pad is provided with
wear indicator grooves, which allow
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator grooves. If a brake
pad has worn to the point that the wear
1. Rear brake light switch
2. Rear brake light switch adjusting nut
1. Brake pad wear indicator groove
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-23
6 indicator grooves have almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
EAU22500
Rear brake pads
Check each rear brake pad for damage
and measure the lining thickness. If a
brake pad is damaged or if the lining
thickness is less than 1.0 mm (0.04 in),
have a Yamaha dealer replace the
brake pads as a set.
EAU22580
Checking the brake fluid level Front brake
Rear brake
Insufficient brake fluid may allow air to
enter the brake system, possibly caus-
ing it to become ineffective.Before riding, check that the brake fluid
is above the minimum level mark and
replenish if necessary. A low brake fluid
level may indicate worn brake pads
and/or brake system leakage. If the
brake fluid level is low, be sure to check
the brake pads for wear and the brake
system for leakage.
Observe these precautions:
When checking the fluid level,
make sure that the top of the brake
fluid reservoir is level.
Use only the recommended quality
brake fluid, otherwise the rubber
seals may deteriorate, causing
leakage and poor braking perfor-
mance.
Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor braking performance.
1. Lining thickness
1. Minimum level mark
1. Minimum level mark
Recommended brake fluid:
DOT 4
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PERIODIC MAINTENANCE AND MINOR REPAIR
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6
Be careful that water does not en-
ter the brake fluid reservoir when
refilling. Water will significantly
lower the boiling point of the fluid
and may result in vapor lock.
Brake fluid may deteriorate paint-
ed surfaces or plastic parts. Al-
ways clean up spilled fluid
immediately.
As the brake pads wear, it is nor-
mal for the brake fluid level to grad-
ually go down. However, if the
brake fluid level goes down sud-
denly, have a Yamaha dealer
check the cause.
EAU22760
Drive chain slack The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22782
To check the drive chain slack
1. Place the motorcycle on the side-
stand.NOTE:When checking and adjusting the drive
chain slack, there should be no weighton 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.
NOTE:When checking the drive chain slack,
the chain tensioner should not betouching the drive chain.
EAU22932
To adjust the drive chain slack
(XT660R)
1. Loosen the axle nut, then loosen
the locknut at each end of the
swingarm.
2. To tighten the drive chain, turn the
adjusting nut at each end of the
swingarm in direction (a). To loos-
en the drive chain, turn the adjust-
ing nut at each end of the
swingarm in direction (b), and then
push the rear wheel forward.
1. Drive chain slack
Drive chain slack:
40.0–55.0 mm (1.57–2.17 in)
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PERIODIC MAINTENANCE AND MINOR REPAIR
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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
EAU23022
Cleaning and lubricating the
drive chain The drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly wear
out, especially when riding in dusty or
wet areas. Service the drive chain as
follows.CAUTION:
ECA10581
The drive chain must be lubricated
after washing the motorcycle andriding in the rain.
1. Clean the drive chain with kero-
sene and a small soft brush.CAUTION:
ECA11120
To prevent damaging the O-rings, do
not clean the drive chain with steam
cleaners, high-pressure washers orinappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant.
CAUTION:
ECA11110
Do not use engine oil or any other lu-
bricants for the drive chain, as they
may contain substances that coulddamage the O-rings.
Tightening torques:
Locknut:
16 Nm (1.6 m·kgf, 11 ft·lbf)
Axle nut:
104 Nm (10.4 m·kgf, 75 ft·lbf)
U5VKE1E0.book Page 26 Tuesday, July 18, 2006 1:00 PM