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7
To install the spark plu
g
1. Clean the surface of the spark plug gasket and its mating sur-
face, and then wipe off any grime
from the spark plug threads.
2. Install the spark plug with the spark plug wrench, and then tight-
en it to the specified torque.
TIPIf a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is 1/4…
1/2 turn past finger tight. However, the
spark plug should be tightened to the
specified torque as soon as possible.3. Install the spark plug cap asshown.
EAU4144C
Transmission oilThe transmission must be checked for
oil leakage before each ride. If any
leakage is found, have a Yamaha deal-
er check and repair the motorcycle. In
addition, the transmission oil must be
changed at the intervals specified in
the periodic maintenance and lubrica-
tion chart.1. Start the engine, warm it up for several minutes, and then turn it
off.
2. Place the motorcycle on a level surface and hold it in an upright
position.
3. Place an oil pan under the trans- mission case to collect the used
oil.
4. Remove the transmission oil filler cap and its O-ring, and then re-
move the transmission oil drain
bolt and its gasket to drain the oil
from the transmission.
Tightenin g torque:
Spark plug: 20 N·m (2.0 kgf·m, 15 lb·ft)
1. Spark plug cap
1
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Periodic maintenance an d a djustment
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7
5. Install the drain bolt and its new
gasket, and then tighten the bolt
to the specified torque.
6. Refill with the specified amount of the recommended transmission
oil.
NOTICE
ECA10453
In or der to prevent clutch slip-
pa ge (since the transmission oil
also lu bricates the clutch), d o
not mix any chemical additives.
Do not use oils with a d iesel
specification of “CD” or oils of a
hi gher quality than specifie d. In
a ddition, do not use oils la beled
“ENERGY CONSERVING II” or
hi gher.
Make sure that no forei gn mate-
rial enters the transmission.7. Check the O-ring for damage, and replace it if necessary.
8. Install and tighten the transmis- sion oil filler cap and its O-ring.
9. Start the engine, and then let it idle for several minutes while checking
it for oil leakage. If oil is leaking,
immediately turn the engine off
and check for the cause.
EAU20071
CoolantThe coolant level should be checked
before each ride. In addition, the cool-
ant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAUM1296
To check the coolant level1. Place the vehicle on a level sur- face and hold it in an upright posi-
tion.TIPThe coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to the
side can result in a false reading.2. Remove the radiator cap and
check the coolant level in the radi-
ator. WARNING! Never attempt
to remove the ra diator cap
when the en gine is hot.
[EWA10382]
1. Transmission oil filler cap
2. O-ring
3. Transmission oil drain bolt
4. GasketTi ghtenin g torque:
Transmission oil drain bolt: 10 N·m (1.0 kgf·m, 7.4 lb·ft)
12
4
3
Recommen ded transmission oil:
Motor oil SAE 10W-40 type SG or
higher
Oil chan ge quantity:
0.50 L (0.53 US qt, 0.44 Imp.qt)
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Periodic maintenance an d a djustment
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7
TIPThe coolant should be at the bottom of
the radiator filler neck. The level will
change with variation of engine tem-
perature.
3. If the coolant is below the correct
coolant level, add coolant, and
then install the radiator cap.
NOTICE: If coolant is not avail-
a b le, use d istilled water or soft
tap water instea d. Do not use
har d water or salt water since it
is harmful to the en gine. If water
has been used instead of cool-
ant, replace it with coolant as
soon as possi ble, otherwise the
coolin g system will not b e pro-
tected against frost an d corro-
sion. If water has b een added to
the coolant, have a Yamaha
d ealer check the antifreeze con-
tent of the coolant as soon as
possi ble, otherwise the effec-
tiveness of the coolant will be
re duce d.
[ECA10473]
EAUM1318
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 en- gine to collect the used coolant. 3. Remove the radiator cap, and
then the coolant drain bolt and its
gasket to drain the cooling sys-
tem. WARNING! Never attempt
to remove the ra diator cap
when the en gine is hot.
[EWA10382]
1. Radiator cap
1. Correct coolant level
11
1
1. Radiator cap
1. Coolant drain bolt
2. Gasket
11
2
1
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Periodic maintenance an d a djustment
7-11
7 4. After the coolant is completely
drained, thoroughly flush the cool-
ing system with clean tap water.
5. Install the coolant drain bolt and its new gasket, and then tighten
the bolt to the specified torque.
6. Pour the recommended coolant into the radiator until it is full.
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.
EAU48394
Cleanin g the air filter elementThe air filter element should be cleaned
or replaced at the intervals specified in
the periodic maintenance and lubrica-
tion chart. Clean or, if necessary, re-
place the air filter element more
frequently if you are riding in unusually
wet or dusty areas.
1. Remove the seat. (See page 4-7.)
2. Remove the air filter element by removing the wing bolt and its
washer.
3. Remove the sponge material from the air filter element frame.
Tightenin g torque:
Coolant drain bolt: 10 N·m (1.0 kgf·m, 7.4 lb·ft)
Antifreeze/water mixture ratio: 1:1
Recommen ded antifreeze:
High-quality ethylene glycol anti-
freeze containing corrosion inhibi-
tors for aluminum engines
Coolant quantity: Radiator (including all routes):0.50 L (0.53 US qt, 0.44 Imp.qt)
1. Wing bolt
2. Washer
3. Air filter element
1 1
3 32
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Periodic maintenance an d a djustment
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7
4. Clean the sponge material with
solvent, and then squeeze the re-
maining solvent out.
5. Apply oil of the recommended type to the entire surface of the
sponge material, and then
squeeze the excess oil out.
TIPThe sponge material should be wet but
not dripping.6. Pull the sponge material over theair filter element frame.
7. Insert the air filter element into the air filter case with the projection
facing upward, and then install the
wing bolt and its washer.
NOTICE: Make sure that the air
filter element is properly seated
in the air filter case. The en gine
shoul d never b e operated with-
out the air filter element in-
stalle d, otherwise the piston(s)
an d/or cylin der(s) may become
excessively worn.
[ECA10482]
NOTICE: Be sure to install the
washer with its curved side fac-
in g outwar d as shown.
[ECA16692]
8. Install the seat.
1. Sponge material
2. Air filter element frame
1
2
Recommended oil:
Yamaha foam air filter oil or other
quality foam air filter oil
1. Air filter element
2. Projection
1. Washer
1 1
2 2
1
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Periodic maintenance an d a djustment
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7
EAU42111
A djustin g the car buretorThe carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
carburetor adjustments should be left
to a Yamaha dealer, who has the nec-
essary professional knowledge and ex-
perience. The adjustment described in
the following section, however, may be
serviced by the owner as part of rou-
tine maintenance.NOTICE
ECA10551
The car buretor has been set an d ex-
tensively teste d at the Yamaha fac-
tory. Chang ing these settin gs
without sufficient technical knowl-
e dge may result in poor perfor-
mance of or d amage to the en gine.
EAU44391
A djustin g the eng ine idlin g
spee dThe 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).
EAU48434
Adjustin g the throttle grip free
playMeasure the throttle grip free play as
shown.
Periodically check the throttle grip free
play and, if necessary, adjust it as fol-
lows.TIPThe engine idling speed must be cor-
rectly adjusted before checking and
adjusting the throttle grip free play.1. Slide the rubber cover back.
2. Loosen the locknut.
1. Throttle stop screw
11
(a)(a)
(b)(b)
(a) (b)
1. Throttle grip free playThrottle
grip free play:
3.0–6.0 mm (0.12–0.24 in)
11
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Periodic maintenance an d a djustment
7-14
7
3. To increase the throttle grip free
play, turn the adjusting nut in di-
rection (a). To decrease the throt-
tle grip free play, turn the adjusting
nut in direction (b).
4. Tighten the locknut and then slide the rubber cover to its original po-
sition.
EAU65042
TiresTires are the only contact between the
vehicle and the road. Safety in all con-
ditions of riding depends on a relatively
small area of road contact. Therefore, it
is essential to maintain the tires in good
condition at all times and replace them
at the appropriate time with the speci-
fied tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
WARNING
EWA14382
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or d eath from loss of
control. The tire air pressure must b e
checked and a djuste d on col d
tires (i.e., when the temperature
of the tires equals the am bient
temperature).
The tire air pressure must be
a d juste d in accor dance with the
wei ght of the ri der, the ri din g
speed , and the ri din g con di-
tions.
Tire inspection
The tires must be checked before each
ride.
1. Locknut
2. Throttle grip free play adjusting nut
3. Rubber cover
321
(b) (b) (b)
(a) (a) (a)
Stan
dar d tire air pressure:
Front: 100 kPa (1.00 kgf/cm², 15 psi)
Rear:
100 kPa (1.00 kgf/cm², 15 psi)
1. Tire sidewall
2. Tire tread depth
12
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Periodic maintenance an d a djustment
7-15
7
NOTICE
ECA15582
Make sure the bead stopper is
ti g htene d. A loose bead stopper
will cause the tire to slip off the
rim if tire pressure is too low.
Make sure the valve stem is po-
sitioned straight. A tilte d valve
stem in dicates that the tire has
slippe d from its ori ginal position
on the rim. Rotate the tire so
that the valve stem is positione d
straig ht.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 model is equipped with tube tires.
Tires age, even if they have not been
used or have only been used occasion-
ally. Cracking of the tread and sidewall rubber, sometimes accompanied by
carcass deformation, is an evidence of
ageing. Old and aged tires shall be
checked by tire specialists to ascertain
their suitability for further use.
WARNING
EWA10462
The front an
d rear tires shoul d b e of
the same make an d d esi gn, other-
wise the han dlin g characteristics of
the vehicle may b e different, which
coul d lea d to an acci dent.After extensive tests, only the tires list-
ed below have been approved for this
model by Yamaha.
WARNING
EWA14391
Have a Yamaha dealer replace
excessively worn tires. Operat-
in g the motorcycle with exces-
sively worn tires d ecreases
ri din g sta bility an d can lead to
loss of control.
The replacement of all wheel-
and b rake-relate d parts, inclu d-
in g the tires, shoul d b e left to a
Yamaha dealer, who has the
necessary professional knowl-
e dge an d experience.
It is not recommen ded to patch
a punctured tube. If unavoi d-
a b le, however, patch the tu be
very carefully an d replace it as
soon as possi ble with a hi gh-
quality pro duct.
Minimum tire trea d d epth (front an d
rear):
4.0 mm (0.16 in)
Front tire:Size:70/100-17 40M (YZ85, YZ85N)
70/100-19 42M (YZ85LW,
YZ85LWN)
Manufacturer/model:
DUNLOP/MX3SF
Rear tire:
Size:90/100-14 49M (YZ85, YZ85N)
90/100-16 52M (YZ85LW,
YZ85LWN)
Manufacturer/model: DUNLOP/MX3S
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