2013 YAMAHA YZ85 engine

PERIODIC MAINTENANCE AND ADJUSTMENT
7-9
7To 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. GasketTightening 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)
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 idlefor 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.
EAUM1295
To check the coolant level1. Place the vehicle on a level sur- face and hold it in an upright posi-
tion.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.
2. Remove the radiator cap andcheck the coolant level in the radi-
ator. WARNING! Never attempt
to remove the radiator cap when
the engine is hot.
[EWA10381]
TIPThe coolant should be at the bottom of
the radiator filler neck. The level will
change with variation of engine temper-
ature.1. Radiator cap
1. Correct coolant level
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-11
73. If the coolant is below the correct
coolant level, add coolant, and
then install the radiator cap.
NOTICE: If coolant is not avail-
able, 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 cool-
ant, replace it with coolant as
soon as possible, otherwise the
cooling system will not be pro-
tected against frost and corro-
sion. If water has been added to
the coolant, have a Yamaha
dealer check the antifreeze con-
tent of the coolant as soon as
possible, otherwise the effec-
tiveness 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 completelydrained, 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
1. Coolant drain bolt
2. Gasket
1. Radiator cap
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
7
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.
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
75. 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 oil1. Air filter element seat
1
1. Air filter element
2. Projection
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PERIODIC MAINTENANCE AND ADJUSTMENT
7-14
7
10. 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.
EAU41822
Tires Tires 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
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).
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
7-24
7
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] EAU23114
Checking and lubricating the
throttle grip and cable The operation of the throttle grip should
be checked before each ride. In addi-
tion, the cable should be lubricated by a
Yamaha dealer at the intervals speci-
fied in the periodic maintenance chart.
The throttle cable is equipped with a
rubber cover. Make sure that the cover
is securely installed. Even though the
cover is installed correctly, it does not
completely protect the cable from water
entry. Therefore, use care not to pour
water directly onto the cover or cable
when washing the vehicle. If the cable
or cover becomes dirty, wipe clean with
a moist cloth.
EAU23143
Checking and lubricating the
brake and clutch levers The operation of the brake and clutch
levers should be checked before each
ride, and the lever pivots should be lu-
bricated if necessary.
Brake lever
Clutch lever
Recommended lubricant:
Yamaha Chain and Cable Lube or 4-
stroke engine oil
U1SN81E0.book Page 24 Tuesday, June 12, 2012 3:17 PM