2012 YAMAHA YZ85 engine

PERIODIC MAINTENANCE AND ADJUSTMENT
7-9
7
To install the spark plug
1. Clean the surface of the spark plug gasket and its mating surface, 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 speci-
fied torque as soon as possible.3. Install the spark plug cap.
EAU41448
Transmission oil The 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 lubrication
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 po-
sition.
3. Place an oil pan under the trans- mission case to collect the used
oil.
4. Remove the oil filler cap, the trans- mission oil drain bolt and its gasket
to drain the oil from the transmis-
sion. 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, and then install and tighten the
oil filler cap.
Tightening torque:Spark plug:20 Nm (2.0 m ·kgf, 14 ft ·lbf)
1. Transmission oil filler cap
2. Transmission oil drain bolt
3. Gasket
Tightening torque:
Transmission oil drain bolt:
10 Nm (1.0 m ·kgf, 7.2 ft ·lbf)
Recommended transmission oil: See page 9-1.
Oil change quantity: 0.50 L (0.53 US qt, 0.44 Imp.qt)
2 1
2
3
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-10
7
NOTICE
ECA10452


In order to prevent clutch slip-
page (since the transmission oil
also lubricates the clutch), do
not mix any chemical additives.
Do not use oils with a diesel
specification of “CD ” or oils of a
higher quality than specified. In
addition, do not use oils labeled
“ ENERGY CONSERVING II ” or
higher.


Make sure that no foreign mate-
rial enters the transmission.
7. Start the engine, and then let it idle for several minutes while checking
it for oil leakage. If oil is leaking, im-
mediately turn the engine off and
check for the cause.
EAU20070
Coolant The 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.
EAUM1294
To check the coolant level1. Place the vehicle on a level sur- face and hold it in an upright posi-
tion.
2. Remove the radiator cap and check the coolant level in the radi-
ator. WARNING! Never attempt
to remove the radiator cap when
the engine is hot.
[EWA10381]
TIP

The coolant level must be checked
on a cold engine since the level
varies with engine temperature.


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.
TIPThe coolant should be at the bottom of
the radiator filler neck. The level will
change with variation of engine temper-
ature.3. If the coolant is below this level, add coolant, and then install the
radiator cap. NOTICE: If coolant
1. Radiator cap
1. Correct coolant level
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-11
7
is not available, use distilled wa-
ter 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 anti- freeze content of the coolant as
soon as possible, otherwise the
effectiveness of the coolant will
be reduced.
[ECA10472]
EAUM1315
To change the coolant1. 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.
3. Remove the coolant drain bolt and its gasket, and then the radiator
cap to drain the cooling system. WARNING! Never attempt to re-
move the radiator cap when the
engine is hot.
[EWA10381]
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.1. Coolant drain bolt
2. Gasket
1. Radiator cap
1
1
2
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 inhibi-
tors 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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PERIODIC MAINTENANCE AND ADJUSTMENT
7-12
79. Start the engine, and then check
the vehicle for coolant leakage. If
coolant is leaking, have a Yamaha
dealer check the cooling system.
EAU48391
Cleaning the air filter element The 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 case cover as shown. 3. Remove the air filter element by
removing the wing bolt and its
washer.
4. Remove the sponge material from the air filter element frame.1. Air filter case cover
1. Wing bolt
2. Washer
3. Air filter element
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-13
7
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.
TIPThe sponge material should be wet but
not dripping.7. Pull the sponge material over theair filter element frame.
8. Apply all-purpose grease to the air filter element seat.
9. 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 ele-
ment is properly seated in the air filter case. The engine
should never be operated with-
out the air filter element in-
stalled, otherwise the piston(s)
and/or cylinder(s) may become
excessively worn.
[ECA10481]
NOTICE:
Be sure to install the
washer with its curved side fac-
ing outward as shown.
[ECA16691]
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 seat
1
1. Air filter element
2. Projection
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-14
710. Install the air filter case cover in the
original position as shown.
11. Install the seat.
EAU42110
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.NOTICE
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. Washer
1
1. Throttle stop screw
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-15
7
EAU48432
Adjusting the throttle grip free
play The throttle grip free play should mea-
sure 3.0–5.0 mm (0.12 –0.20 in) at the
inner edge of the throttle grip. Periodi-
cally check the throttle grip free play
and, if necessary, adjust it as follows.TIPThe engine idling speed must be cor-
rectly adjusted before checking and ad-
justing the throttle grip free play.1. Slide the rubber cover back.
2. Loosen the locknut. 3. To increase the throttle grip free
play, turn the adjusting nut in direc-
tion (a). To decrease the throttle
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.
EAU41821
Tires To maximize the performance, durabil-
ity, and safe operation of your motorcy-
cle, 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
EWA14381
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or death from loss of
control.

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 grip free play
1. Locknut
2. Throttle grip free play adjusting nut
3. Rubber cover
2
3
(a)
(b)
1
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-23
7
4. Make sure that the drive chain pull-
ers are in the same position, the
drive chain slack is correct, and
the drive chain moves smoothly.
EAU23016
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.NOTICE
ECA10583
The drive chain must be lubricated
after washing the motorcycle, riding
in the rain or riding in wet areas.1. Remove all dirt and mud from thedrive chain with a brush or cloth.TIPFor a thorough cleaning, have a
Yamaha dealer remove the drive chain
and soak it in solvent.2. Spray Yamaha Chain and CableLube or a high-quality spray-type
drive chain lubricant on the entire
chain, making sure that all side
plates and rollers have been suffi-
ciently oiled.
EAU50800
Checking and lubricating the
cables The operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubricat-
ed if necessary. If a cable is damaged
or does not move smoothly, have a
Yamaha dealer check or replace it.
WARNING! Damage to the outer
housing of cables may result in in-
ternal rusting and cause interfer-
ence with cable movement. Replace
damaged cables as soon as possi-
ble to prevent unsafe conditions.[EWA10711]
Tightening torques:Locknut:
16 Nm (1.6 m ·kgf, 12 ft ·lbf)
Axle nut:
90 Nm (9.0 m ·kgf, 65 ft ·lbf)
Recommended lubricant:
Yamaha Chain and Cable Lube or 4-
stroke engine oil
U1SN80E0.book Page 23 Thursday, June 9, 2011 11:24 AM