light YAMAHA YZ85 2021 Owners Manual

Safety information
2-3
2
ventilated areas. If you experience any
symptoms of carbon monoxide poi-
soning, leave the area immediately, get
fresh air, and SEEK MEDICAL TREAT-
MENT.
 Do not run engine indoors. Even if
you try to ventilate engine exhaust
with fans or open windows and
doors, carbon monoxide can rap-
idly reach dangerous levels.
 Do not run engine in poorly venti-
lated or partially enclosed areas
such as barns, garages, or car-
ports.
 Do not run engine outdoors where
engine exhaust can be drawn into
a building through openings such
as windows and doors.
Genuine Yamaha Accessories
Choosing accessories for your vehicle
is an important decision. Genuine
Yamaha accessories, which are avail- able only from a Yamaha dealer, have
been designed, tested, and approved
by Yamaha for use on your vehicle.
Many companies with no connection
to Yamaha manufacture parts and ac-
cessories or offer other modifications
for Yamaha vehicles. Yamaha is not in
a position to test the products that
these aftermarket companies produce.
Therefore, Yamaha can neither en-
dorse nor recommend the use of ac-
cessories not sold by Yamaha or
modifications not specifically recom-
mended by Yamaha, even if sold and
installed by a Yamaha dealer. Aftermarket Parts, Accessories, an
d
Mo difications
While you may find aftermarket prod-
ucts similar in design and quality to
genuine Yamaha accessories, recog-
nize that some aftermarket accesso-
ries or modifications are not suitable
because of potential safety hazards to
you or others. Installing aftermarket
products or having other modifications
performed to your vehicle that change
any of the vehicle’s design or operation
characteristics can put you and others
at greater risk of serious injury or
death. You are responsible for injuries
related to changes in the vehicle.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.  Never install accessories that
would impair the performance of
your motorcycle. Carefully inspect
the accessory before using it to
make sure that it does not in any
way reduce ground clearance or
cornering clearance, limit suspen-
sion travel, steering travel or con-
trol operation.
• Accessories fitted to the han- dlebar or the front fork area can
create instability due to improp-
er weight distribution. If acces-
sories are added to the
handlebar or front fork area,
they must be as lightweight as
possible and should be kept to
a minimum.
• Bulky or large accessories may seriously affect the stability of
the motorcycle. Wind may at-
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Safety information
2-4
2tempt to lift the motorcycle, or
the motorcycle may become
unstable in cross winds.
• Certain accessories can dis- place the operator from his or
her normal riding position. This
improper position limits the
freedom of movement of the
operator and may limit control
ability, therefore, such accesso-
ries are not recommended.
 Use caution when adding electri-
cal accessories. If electrical ac-
cessories exceed the capacity of
the motorcycle’s electrical sys-
tem, an electric failure could re-
sult, which could cause a
dangerous loss of lights or engine
power.
Aftermarket Tires an d Rims
The tires and rims that came with your
motorcycle were designed to match
the performance capabilities and to
provide the best combination of han-
dling, braking, and comfort. Other
tires, rims, sizes, and combinations
may not be appropriate. Refer to page
7-14 for tire specifications and more in-
formation on replacing your tires.
Transportin g the Motorcycle
Be sure to observe following instruc-
tions before transporting the motorcy-
cle in another vehicle.  Remove all loose items from the
motorcycle.
 Check that the fuel cock (if
equipped) is in the “OFF” position
and that there are no fuel leaks. 
Point the front wheel straight
ahead on the trailer or in the truck
bed, and choke it in a rail to pre-
vent movement.
 Shift the transmission in gear (for
models with a manual transmis-
sion).
 Secure the motorcycle with tie-
downs or suitable straps that are
attached to solid parts of the mo-
torcycle, such as the frame or up-
per front fork triple clamp (and not,
for example, to rubber-mounted
handlebars or turn signals, or
parts that could break). Choose
the location for the straps carefully
so the straps will not rub against
painted surfaces during transport.
 The suspension should be com-
pressed somewhat by the tie-
downs, if possible, so that the mo-
torcycle will not bounce exces-
sively during transport.
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Instrument and control functions
4-1
4
EAU40661
Han dle bar switch
EAU53962En gine stop switch “ENGINE STOP”
Hold this switch pushed until the en-
gine stops.
EAU64023
Clutch lever
The clutch lever is located on the left
side of the handlebar. To disengage
the clutch, pull the lever toward the
handlebar grip. To engage the clutch,
release the lever. The lever should be
pulled rapidly and released slowly for
smooth clutch operation.
The clutch lever is equipped with a
clutch lever position adjusting bolt. Ad-
just the distance between the clutch le-
ver and the handlebar grip as follows. 1. Loosen the locknut.
2. While holding the clutch lever pulled slightly towards the handle-
bar grip, turn the adjusting bolt in
direction (a) to increase the dis-
tance, and in direction (b) to de-
crease it.
3. Tighten the locknut.
1. Engine stop switch “ENGINE STOP”
1. Clutch lever
2. Locknut
3. Clutch lever position adjusting bolt
4. Distance between clutch lever and handle- bar grip
4 2
13
(b)
(a)
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Instrument and control functions
4-5
4 Gasoline
This model’s engine is designed to use
premium unleaded gasoline with a
pump octane number [(R+M)/2] of 91
or higher, or a research octane number
(RON) of 95 or higher. If knocking or
pinging occurs, try a gasoline of a dif-
ferent brand.
NOTICE
ECA15591
Use only unlea
ded g asoline. The use
of lea ded g asoline will cause severe
d amag e to internal en gine parts,
such as the piston rin gs as well as to
the exhaust system.
Gasohol
There are two types of gasohol: gaso-
hol containing ethanol and that con-
taining methanol. Gasohol containing
ethanol can be used if the ethanol con-
tent does not exceed 10% (E10). Gas-
ohol containing methanol should not
be used as it can cause engine or fuel
system problems.
Fillin g the fuel tank
WARNING
EWA10882
Gasoline an d gasoline vapors are
extremely flammab le. To avoid fires
an d explosions an d to re duce the
risk of injury when refueling , follow
these instructions.
1. Before refueling, turn off the en- gine and be sure that no one is sit-
ting on the vehicle. Never refuel
while smoking, or while in the vi-
cinity of sparks, open flames, or
other sources of ignition such as
the pilot lights of water heaters
and clothes dryers.
2. Do not overfill the fuel tank. Stop filling when the fuel reaches the
bottom of the filler tube. Because
fuel expands when it heats up,
heat from the engine or the sun
can cause fuel to spill out of the
fuel tank.
3. Wipe up any spilled fuel immedi- ately. NOTICE: Immediately
wipe off spille d fuel with a clean,
d ry, soft cloth, since fuel may
d eteriorate painte d surfaces or
plastic parts.
[ECA10072]
4. Be sure to securely close the fuel tank cap.
WARNING
EWA15152
Gasoline is poisonous an d can
cause injury or death. Han dle gaso-
line with care. Never siphon gasoline
b y mouth. If you shoul d swallow
some gasoline or inhale a lot of gas-
oline vapor, or get some gasoline in
your eyes, see your doctor imme di-
ately. If gasoline spills on your skin,
1. Maximum fuel level
2. Fuel tank filler tube
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Instrument and control functions
4-8
4
EAU13651
Kickstarter
To start the engine, fold out the kick-
starter lever, move it down lightly with
your foot until the gears engage, and
then push it down smoothly but force-
fully. This model is equipped with a pri-
mary kickstarter, allowing the engine to
be started in any gear if the clutch is
disengaged. However, shifting the
transmission into the neutral position
before starting is recommended.
EAU46283
Seat
To remove the seat
Remove the bolts, and then slide the
seat to the rear and pull upward.
To install the seat
1. Fit the slot in the seat onto the pro- jection on the fuel tank, and insert
the projection on the seat into the
seat holder as shown.
2. Place the seat in the original posi- tion, and then tighten the bolts.
TIP
Make sure that the seat is properly se-
cured before riding.
1. Kickstarter lever
1
1. Bolt
1. Slot
2. Projection
3. Seat holder
1
1
2
3
2
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Operation and important ri din g points
6-2
6
the higher gears and check the
full-throttle response. Stop the en-
gine and check the spark plug.
5. After again allowing the engine to cool, restart and run the motorcy-
cle for 5 more minutes. Full throttle
and the higher gears may be used,
but sustained full-throttle opera-
tion should be avoided. Stop the
engine and check the spark plug
again.
6. Allow the engine to cool, remove the cylinder head and cylinder,
and inspect the piston and cylin-
der. Remove any high spots on
the piston with #600-grit wet
sandpaper. Clean all components
and carefully reassemble the cyl-
inder head and cylinder.
7. Drain the break-in oil-fuel mixture from the fuel tank and refill with
the normal oil-fuel mixture. (See
page 4-4.)
8. Start the engine and check its power delivery and throttle re-
sponse throughout all gear rang-
es. Stop the engine and check the
spark plug condition. It should be-
gin to lighten in color.
9. Restart the motorcycle and ride it for about 10 to 15 more minutes.
Stop the engine and check the
spark plug condition. (See page
7-6.)
10. Lastly, thoroughly check the mo- torcycle for loose parts, oil leak-
age and any other problems.
Check all fittings and fasteners
and tighten as necessary.
TIP
Be sure to inspect and make adjust-
ments thoroughly. In particular, check
control cable slack, drive chain slack
and for loose spokes.
Notes on en gine overhauls
If the following parts have been re-
placed, they must be broken in as fol-
lows.  Piston, rings or transmission
gears: 30 minutes of break-in op-
eration at half-throttle or less.
 Cylinder or crankshaft: 60 minutes
of break-in operation is necessary.
TIP
Observe the condition of the engine
carefully during break-in operation.
NOTICE
ECA10271
If any en gine trou ble shoul d occur
d urin g the en gine break-in perio d,
imme diately have a Yamaha dealer
check the vehicle.
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Operation and important rid ing points
6-3
6
EAU41308
Startin g an d warmin g up a
col d en gine
1. Turn the fuel cock lever to “ON”.
2. Shift the transmission into the
neutral position.
3. Turn the starter (choke) on and completely close the throttle. (See
page 4-7.)
4. Start the engine by pushing the kickstarter lever down.
5. When the engine is warm, turn the starter (choke) off.
TIP
The engine is warm when it responds
quickly to the throttle with the starter
(choke) turned off.
NOTICE
ECA11043
For maximum en gine life, never ac-
celerate har d when the en gine is
col d!
EAU16661
Startin g a warm en gine
Follow the same procedure as for
starting a cold engine with the excep-
tion that the starter (choke) is not re-
quired when the engine is warm.
Instead, start the engine with the throt-
tle slightly open.
TIP
If the engine does not start after sever-
al kicks, try again with the throttle 1/4
to 1/2 open.
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Operation and important ri din g points
6-4
6
EAU16674
Shiftin g
Shifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing hills,
etc.
The gear positions are shown in the il-
lustration.
TIP
To shift the transmission into the neu-
tral position ( ), press the shift pedal
down repeatedly until it reaches the
end of its travel, and then slightly raise
it.
NOTICE
ECA10261
Even with the transmission in
the neutral position, d o not
coast for lon g period s of time
with the en gine off, an d d o not
tow the motorcycle for lon g d is-
tances. The transmission is
properly lu bricated only when
the en gine is runnin g. Ina de-
quate lu brication may damag e
the transmission.
 Always use the clutch while
chan gin g g ears to avoi d d am-
a g in g the en gine, transmission, an
d d rive train, which are not
d esi gne d to withstan d the
shock of force d shiftin g.
EAU16691To start out an d accelerate
1. Pull the clutch lever to disengage the clutch.
2. Shift the transmission into first gear.
3. Open the throttle gradually and si- multaneously release the clutch
lever slowly.
4. Once the motorcycle has reached a speed high enough to change
gears, close the throttle, and at the
same time, quickly pull the clutch
lever in.
5. Shift the transmission into second gear. (Make sure not to shift the
transmission into the neutral posi-
tion.)
6. Open the throttle halfway and gradually release the clutch lever.
7. Follow the same procedure when
shifting to the next gear.
EAU16711To decelerate
1. Close the throttle and apply both the front and the rear brakes to
slow the motorcycle.
2. Downshift through the gears and shift the transmission into the neu-
tral position when the motorcycle
is almost completely stopped.
1. Gear positions
2. Shift pedal
2
1
1
N 2 3
4
5
6
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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
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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