YAMAHA YZ85 2008 Workshop Manual
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-11
6 3. If the coolant is below this level,
add coolant, and then install the
radiator cap.
NOTE:
If the engine overheats, see page 6-31for further instructions.
EAUM1312
To change the coolant
1. Place the vehicle on a level sur-
face and let the engine cool if nec-
essary.
2. Place a container under the engine
to collect the used coolant.
WARNING
EWA10380
Never attempt to remove the radiatorcap when the engine is hot.
3. Remove the coolant drain bolt and
then the radiator cap to drain the
cooling system.4. After the coolant is completely
drained, thoroughly flush the cool-
ing system with clean tap water.
5. Install the coolant drain bolt, and
then tighten it to the specified
torque.
NOTE:Check the washer for damage and re-place it if necessary.
6. Pour the recommended coolant
into the radiator until it is full.
1. Correct coolant level
1. Coolant drain bolt
1. Radiator cap
Tightening torque:
Coolant drain bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Antifreeze/water mixture ratio:
1:1
Recommended antifreeze:
High-quality ethylene glycol anti-
freeze containing corrosion inhibitors
for aluminum engines
Coolant quantity:
Radiator capacity (including all
routes):
0.54 L (0.57 US qt) (0.48 Imp.qt)
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6-12
6
CAUTION:
ECA10471
If coolant is not available, use
distilled water or soft tap water
instead. Do not use hard water
or salt water since it is harmful
to the engine.
If water has been used instead
of coolant, replace it with cool-
ant as soon as possible, other-
wise the cooling system will not
be protected against frost and
corrosion.
If water has been added to the
coolant, have a Yamaha dealer
check the antifreeze content of
the coolant as soon as possible,
otherwise the effectiveness ofthe coolant will be reduced.
7. Install the radiator cap, start the
engine, let it idle for several min-
utes, and then turn it off.
8. Remove the radiator cap to check
the coolant level in the radiator. If
necessary, add sufficient coolant
until it reaches the bottom of the
radiator filler neck, and then install
the radiator cap.9. Start the engine, and then check
the vehicle for coolant leakage. If
coolant is leaking, have a Yamaha
dealer check the cooling system.
EAU41431
Cleaning the air filter element The air filter element should be cleaned
at the intervals specified in the periodic
maintenance and lubrication chart.
Clean the air filter element more fre-
quently if you are riding in unusually
wet or dusty areas.
1. Remove the seat. (See page 3-6.)
2. Remove the air filter case cover as
shown.1. Air filter case cover
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-13
6 3. Remove the air filter element by
removing the wing bolt and wash-
er.
4. Remove the sponge material from
the air filter element frame.5. Clean the sponge material with
solvent, and then squeeze the re-
maining solvent out.
6. Apply oil of the recommended type
to the entire surface of the sponge
material, and then squeeze the ex-
cess oil out.
NOTE:The sponge material should be wet butnot dripping.
7. Pull the sponge material over the
air filter element frame.
8. Insert the air filter element into the
air filter case with the projection
facing upward, and then install the
washer and wing bolt.
1. Wing bolt
2. Washer
3. Sponge material
1. Sponge material
2. Air filter element frame
Recommended oil:
Yamaha foam air filter oil or other
quality foam air filter oil
1. Sponge material
2. Projection
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6-14
6
CAUTION:
ECA10480
Make sure that the air filter ele-
ment is properly seated in the
air filter case.
The engine should never be op-
erated without the air filter ele-
ment installed, otherwise the
piston(s) and/or cylinder(s) maybecome excessively worn.
9. Install the air filter case cover in the
original position as shown.
10. Install the seat.
EAU39930
Adjusting the carburetor The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most car-
buretor adjustments should be left to a
Yamaha dealer, who has the neces-
sary professional knowledge and expe-
rience. The adjustment described in the
following section, however, may be ser-
viced by the owner as part of routine
maintenance.CAUTION:
ECA10550
The carburetor has been set and ex-
tensively tested at the Yamaha fac-
tory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-mance of or damage to the engine.
EAU44390
Adjusting the engine idling
speed The engine idling speed must be ad-
justed when necessary.
1. Start the engine and thoroughly
warm it up.
2. Turn the throttle stop screw until
the engine runs at the lowest pos-
sible speed.
3. To increase the engine idling
speed, turn the throttle stop screw
in direction (a). To decrease the
engine idling speed, turn the throt-
tle stop screw in direction (b).1. Throttle stop screw
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6-15
6
EAU21370
Adjusting the throttle cable
free play The throttle cable free play should mea-
sure 3.0–5.0 mm (0.12–0.20 in) at the
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, adjust it as follows.NOTE:The engine idling speed must be cor-
rectly adjusted before checking and ad-justing the throttle cable free play.
1. Loosen the locknut.2. To increase the throttle cable free
play, turn the adjusting nut in direc-
tion (a). To decrease the throttle
cable free play, turn the adjusting
nut in direction (b).
3. Tighten the locknut.
EAU41820
Tires To maximize the performance, durabil-
ity, and safe operation of your motor-
cycle, note the following points
regarding the specified tires.
Tire air pressure
The tire air pressure should be checked
and, if necessary, adjusted before each
ride.
WARNING
EWA14380
The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the temperature
of the tires equals the ambient
temperature).
The tire air pressure must be ad-
justed in accordance with the
weight of the rider, the riding
speed, and the riding condi-tions.
1. Throttle cable free play
1. Locknut
2. Throttle cable free play adjusting nut
Standard tire air pressure:
Front:
100 kPa (15 psi) (1.00 kgf/cm²)
Rear:
100 kPa (15 psi) (1.00 kgf/cm²)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-16
6Tire inspection
The tires must be checked before each
ride.
CAUTION:
ECA15580
Be sure the bead stoppers are
tightened. Loose bead stoppers
will cause the tire to slip off the
rim if tire pressure is too low.
Be sure the valve stem is posi-
tioned straight. A tilted valve
stem indicates that the tire has
slipped from its original posi-
tion on the rim. Rotate the tire
so that the valve stem is posi-tioned straight.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 information
This motorcycle is equipped with spoke
wheels and 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
EWA14390
Have a Yamaha dealer replace
excessively worn tires. Operat-
ing the motorcycle with exces-
sively worn tires decreases
riding stability and can lead to
loss of control.
1. Tire sidewall
2. Tire tread depth
12
Minimum tire tread depth (front and
rear):
4.0 mm (0.16 in)
Front tire:
Size:
YZ85 70/100-17 40M
YZ85LW 70/100-19 42M
YZ85LWX 70/100-19 42M
YZ85X 70/100-17 40M
Manufacturer/model:
YZ85 DUNLOP/D739FA (ZAF)
YZ85 DUNLOP/D756F
(AUT)(BEL)(CHE)(DEU)(DNK)(ES
P)(FIN)(FRA)(GBR)(GRC)(IRL)(N
LD)(NOR)(PRT)(SWE)
YZ85LW DUNLOP/D756F
YZ85LWX DUNLOP/D756F
YZ85X DUNLOP/D756F
Rear tire:
Size:
YZ85 90/100-14 49M
YZ85LW 90/100-16 52M
YZ85LWX 90/100-16 52M
YZ85X 90/100-14 49M
Manufacturer/model:
DUNLOP/D756
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-17
6
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.
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.
EAU40431
Accessories and replacement
parts
WARNING
EWA14481
The accessories or replacement
parts you choose for your vehicle
should be designed specifically for
this model, and they must be se-
curely mounted to maintain the in-
herent stability of the original
design. Genuine Yamaha Parts and
Accessories are designed and test-
ed to be compatible with your vehi-
cle. Yamaha recommends the use of
Genuine Yamaha Parts and Acces-
sories before making a purchase.
Use of non-Yamaha-approved ac-
cessories or replacement parts may
cause loss of handling stability and
riding safety. Since Yamaha cannot
control the quality of accessories or
parts manufactured by other compa-
nies, Yamaha cannot be held liable
for any consequences caused by
the use of items which have notbeen approved by Yamaha.
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6
EAU22031
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).3. If the specified clutch lever free
play could be obtained as de-
scribed above, tighten the locknut
and skip the rest of the procedure,
otherwise, proceed as follows.
4. Fully turn the adjusting bolt in di-
rection (a) to loosen the clutch ca-
ble.
5. Loosen the locknut further down
the clutch cable.
6. 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).
7. Tighten both locknuts.
EAU37911
Checking the front brake lever
free play There should be no free play at the
brake lever end. If there is free play,
have a Yamaha dealer inspect the
brake system.
WARNING
EWA14210
A soft or spongy feeling in the brake
lever can indicate the presence of air
in the hydraulic system. If there is air
in the hydraulic system, have a
Yamaha dealer bleed the system be-
fore operating the motorcycle. Air in
the hydraulic system will diminish
1. Clutch lever free play
2. Locknut (clutch lever)
3. Adjusting bolt
1. Locknut (clutch cable)
2. Adjusting nut
1. Brake lever free play
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6-19
6 the braking performance, which may
result in loss of control and an acci-
dent.
EAU22311
Checking the front and rear
brake pads Front brake
Rear brakeThe front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart. Each brake pad is
provided with a wear indicator, which
allows you to check the brake pad wear
without having to disassemble the
brake. To check the brake pad wear,
check the position of the wear indicator
while applying the brake. If a brake pad
has worn to the point that the wear indi-
cator almost touches the brake disc,
have a Yamaha dealer replace the
brake pads as a set.1. Brake pad wear indicator
1. Brake pad wear indicator
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6
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.
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.
1. Minimum level mark
1. Minimum level mark
Recommended brake fluid:
DOT 4
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