2021 YAMAHA YZ85 Owners Manual

Periodic maintenance an d a djustment
7-1
7
EAU42074
Periodic inspection, adjustment, and
lubrication will keep your vehicle in the
safest and most efficient condition
possible. Safety is an obligation of the
vehicle owner/operator. The most im-
portant points of vehicle inspection,
adjustment, and lubrication are ex-
plained on the following pages.
The intervals given in the periodic
maintenance and lubrication chart
should be simply considered as a gen-
eral guide under normal riding condi-
tions. However, depending on the
weather, terrain, geographical location,
and individual use, the maintenance in-
tervals may need to be shortened.
WARNING
EWA10322
Failure to properly maintain the vehi-
cle or performin g maintenance ac-
tivities incorrectly may increase
your risk of injury or death during
service or while usin g the vehicle. If
you are not familiar with vehicle ser-
vice, have a Yamaha d ealer perform
service.
WARNING
EWA15123
Turn off the en gine when performin g
maintenance unless otherwise
specified .
 A runnin g en gine has movin g
parts that can catch on body
parts or clothin g an d electrical
parts that can cause shocks or
fires.
 Runnin g the en gine while ser-
vicin g can lead to eye injury,
b urns, fire, or car bon monoxi de
poisonin g – possi bly lea din g to d
eath. See pag e 2-2 for more in-
formation a bout car bon monox-
i d e.
WARNING
EWA15461
Brake discs, calipers, drums, an d
linin gs can b ecome very hot durin g
use. To avoi d possi ble burns, let
b rake components cool before
touching them.
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Periodic maintenance an d a djustment
7-2
7
EAU66354
Perio dic maintenance an d lu brication chart
The following chart is intended as a general guide to maintenance and lubrication.
Bear in mind that such factors as weather, terrain, geographical location, and in-
dividual usage will alter the required maintenance and lubrication intervals. If you
are in doubt as to what intervals to follow in maintaining and lubricating your mo-
torcycle, consult your Yamaha dealer.
TIP
Items marked with an asterisk should be performed by a Yamaha dealer as they
require special tools, data and technical skills.
NO. ITEM ROUTINEAfter
break-in
Everyrace
Every
third race
Every
fifth race
As
required
1 *Piston Check piston for carbon deposits and
cracks or damage. Clean.
Replace.

2 *
Piston rings Check piston ring end gap and rings
for damage.
Replace.
3 *
Piston pin and small
end bearing Check piston pin and small end
bearing for damage.
Replace.
4 *
Cylinder head Check cylinder head for carbon
deposits.
 Clean.
Check cylinder head gasket fordamage.
 Tighten cylinder head nuts ifnecessary.
Replace cylinder head gasket.

5 *
Cylinder
6*YPVS Check cylinder for score marks or
wear.


 Clean.
Replace.
Check YPVS for carbon deposits andcracks or damage.
Clean.

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Periodic maintenance an d a djustment
7-3
7
10 *Rotor nut
(flywheel magneto) Tighten.
11 *
Kickstarter system Check idle gear for damage. Replace if necessary.
Check exhaust pipe and muffler for
carbon deposits.

12 *Exhaust system
Clean.
 Check crankshaft for carbon depositsand damage.13 *Crankshaft
Clean.
 


14 *
Carburetor Check carburetor settings and for
obstructions.
Adjust and clean. Check condition.
15Spark plug Clean and regap.
Replace.
 Check chain slack, alignment and
condition.
16 *Drive chain Adjust and thoroughly lubricate chain
with Yamaha chain and cable lube or
equivalent.
Replace.
NO. ITEM ROUTINE
After
break-in
Everyrace
Every
third race
Every
fifth race
As
required
7 *Clutch Check clutch housing, friction plates,
clutch plates and clutch springs for
wear or damage.
Adjust.
Replace.

8 *
Transmission Change the transmission oil. Check transmission for damage. Replace bearings.
9 *Shift forks, guide
bars, shift cam Check all parts for wear and damage. Replace if necessary.
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Periodic maintenance an d a djustment
7-4
7
23 *Front fork Check operation and for oil leakage.
Adjust if necessary.
 Clean dust seal and lubricate with
lithium-soap-based grease.
Replace fork oil.
 Replace oil seals.
NO. ITEM ROUTINE
After
break-in
Everyrace
Every
third race
Every
fifth race
As
required
Check coolant level and for leakage.
17 *
Cooling system Check hoses for cracks or damage. Check radiator cap spring operation. Change coolant.
Every 2 years
Every year Check all chassis fitting and fasteners.
18
*Chassis fasteners
Correct or tighten if necessary.
19Air filter element Clean. Replace.
20 *Frame Clean and check for damage.

21
*Fuel line Clean and check for leakage.
22 *
Brakes Adjust lever position and pedal height.
Lubricate pivot points.
Check brake disk surface.
Check fluid level and for leakage.
Tighten brake disk bolts, caliper bolts,
master cylinder bolts and union bolts.
Replace brake pads.
 Replace brake fluid.
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Periodic maintenance an d a djustment
7-5
7
EAU42012
TIP
 Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid levels.
• Every two years replace the internal components of the brake master cyl- inders and calipers, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
NO. ITEM ROUTINEAfter
break-in
Everyrace
Every
third race
Every
fifth race
As
required
*Shock absorber
assembly Check operation and adjust. Tighten if necessary.
Lubricate with lithium-soap-based
grease.

*Drive chain roller
and support guide Check for wear or damage. Replace if necessary.
*Rear suspension Check operation and tighten if
necessary.
Lubricate with molybdenum disulfidegrease.
Check operation, free play, andtighten if necessary.
*
Steering head Clean and lubricate with
lithium-soap-based grease.
Replace bearings. Check tire air pressure, wheel runout,spokes for looseness, and tires for
wear.

Tighten sprocket bolts if necessary.
*Tires and wheels
Check wheel bearings for looseness. Lubricate wheel bearings with
lithium-soap-based grease.
Replace wheel bearings.
*Moving parts and ca-
bles Lubricate.
*
Throttle grip Check operation. Check throttle grip free play, and
adjust if necessary.
27 *Swingarm pivot
bearings 
Lubricate cable and grip housing.
After washing the motorcycle or riding in the rain.
Lubricate with molybdenum
disulfide grease. Check bearing assemblies for
looseness.
24
25
26
28
29
30
31
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Periodic maintenance an d a djustment
7-6
7
EAU84450
Checkin g the spark plu g
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic main-
tenance and lubrication chart. In addi-
tion, the condition of the spark plug
can reveal the condition of the engine.
To remove the spark plu g
1. Remove the spark plug cap.
2. Remove the spark plug as shown, with a spark plug wrench available
at a Yamaha dealer. To check the spark plu
g
1. Check that the porcelain insulator around the center electrode of the
spark plug is a medium-to-light
tan (the ideal color when the vehi-
cle is ridden normally).
TIP
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electrodeerosion and excessive carbon or
other deposits, and replace it if
necessary.
3. Measure the spark plug gap with a wire thickness gauge and, if nec-
essary, adjust the gap to specifi-
cation.
1. Spark plug cap
1. Spark plug wrench
1
1
Specified spark plu g:
NGK/BR10EG
1. Spark plug gap
Spark plu g g ap:
0.5–0.6 mm (0.020–0.024 in)
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Periodic maintenance an d a djustment
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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.
TIP
If 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 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 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.
5. Install the drain bolt and its new gasket, and then tighten the bolt
to the specified torque.
Tightening torque:
Spark plug: 20 N·m (2.0 kgf·m, 15 lb·ft)
1. Spark plug cap
1
1. Transmission oil filler cap
2. O-ring
3. Transmission oil drain bolt
4. Gasket
1
2
43
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Periodic maintenance an d a djustment
7-8
7 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 diesel
specification of “CD” or oils of a
hi gher quality than specifie d. In
a ddition, do not use oils la bele d
“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
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.
EAUM1296To 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 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]
Ti ghtenin g torque:
Transmission oil drain bolt: 10 N·m (1.0 kgf·m, 7.4 lb·ft)
Recommen ded transmission oil:
Motor oil SAE 10W-30 type SE or
higher or Gear oil SAE 85W GL-3
Oil chan ge quantity:
0.50 L (0.53 US qt, 0.44 Imp.qt)
1. Radiator cap
1
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