2020 YAMAHA YZ85 check engine

Periodic maintenance an d a djustment
7-10
7 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 minu-
tes, 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.
EAU48393
Cleanin g 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 4-8.)
2. Remove the air filter case cover as shown.
3. Remove the air filter element by removing the wing bolt and its
washer.
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):0.55 L (0.58 US qt, 0.48 Imp.qt)
1. Air filter case cover
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Periodic maintenance an d a djustment
7-13
7
EAU44391
A djustin g the eng ine idlin g
spee d
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).
EAU48434
Adjustin g the throttle grip free
play
Measure the throttle grip free play as
shown.
Periodically check the throttle grip free
play and, if necessary, adjust it as fol-
lows.
TIP
The 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.
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).
1. Throttle stop screw
1. Throttle grip free play
Throttle grip free play:
3.0–6.0 mm (0.12–0.24 in)
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Periodic maintenance an d a djustment
7-21
7
EAU51721
Chan gin g the brake flui d
Have a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrica-
tion chart. In addition, have the oil seals
of the master cylinders and calipers as
well as the brake hoses replaced at the
intervals listed below or whenever they
are damaged or leaking.
 Oil seals: Replace every two
years.
 Brake hoses: Replace every four
years.
EAU22762
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU84400To check the d rive chain slack
1. Place the motorcycle on a suitable stand. (See page 7-28.)
2. Confirm the rear wheel is off the ground and the rear shock ab-
sorber is fully extended.
3. Shift the transmission into neutral.
4. Pull up the drive chain until the chain is taut, and then measure
distance A between the top of the
swingarm and the bottom of the
chain as shown.
5. If the drive chain slack is incorrect, adjust it as follows. NOTICE: Im-
proper drive chain slack will
overload the engine as well as
other vital parts of the motorcy-
cle an d can lead to chain slip-
pa ge or breakag e. To prevent
1. Distance A
Distance A:
58.0–68.0 mm (2.28–2.68 in) (YZ85,
YZ85L)
65.0–75.0 mm (2.56–2.95 in)
(YZ85LW, YZ85LWL)
1
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Periodic maintenance an d a djustment
7-32
7
EAU86410
Trou bleshootin g chart
1. FuelThere is enough fuel.
There is no fuel.
Check the ignition.
Supply fuel.The engine does not
start.
Check the ignition.
Open the throttle
halfway and try
starting the engine.
Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug(s).
2. IgnitionWet
Dry
There is compression.
There is no
compression.
The engine does not start.
Have a Yamaha dealer check the vehicle.
Have a Yamaha dealer check the vehicle.
The engine does not
start.
Check the
compression.Have a Yamaha
dealer check the
vehicle.
Remove the spark
plug and check
the electrodes.
Try starting the
engine.
Check the fuel level
in the fuel tank.
3. Compression
UB4B81E0.book Page 32 Friday, March 1, 2019 2:54 PM

Periodic maintenance an d a djustment
7-33
7
EAU86430En gine overheatin g
WARNING
EWAT1041
Do not remove the rad iator cap when the engine an d ra diator are hot.
Scal din g hot flui d an d steam may b e blown out un der pressure, which
coul d cause serious injury. Be sure to wait until the en gine has coole d.
 Place a thick ra g, like a towel, over the rad iator cap, and then slowly ro-
tate the cap counterclockwise to the d etent to allow any residual pres-
sure to escape. When the hissin g soun d has stoppe d, press d own on the
cap while turnin g it counterclockwise, an d then remove the cap.
TIP
If coolant is not available, tap water can be temporarily used instead, provided
that it is changed to the recommended coolant as soon as possible.
Wait until the engine
has cooled.
Check the coolant
level in the reservoir
and radiator.Add coolant.
(See TIP.)
The coolant level is
OK.
There is no leakage.
There is leakage.
The coolant level is
low.
Check the cooling
system for leakage.
Have a Yamaha
dealer check and
repair the cooling
system.
Start the engine. If the engine overheats again,
have a Yamaha dealer check and repair the cooling
system.
UB4B81E0.book Page 33 Friday, March 1, 2019 2:54 PM

Motorcycle care and stora ge
8-4
8
EAU86460
Stora ge
Always store the vehicle in a cool, dry
place. If necessary, protect it against
dust with a porous cover. Be sure the
engine and the exhaust system are
cool before covering the vehicle. If the
vehicle often sits for weeks at a time
between uses, the use of a quality fuel
stabilizer is recommended after each
fill-up.
NOTICE
ECA21170
 Storin g the vehicle in a poorly
ventilate d room or coverin g it
with a tarp, while it is still wet,
will allow water an d humi dity to
seep in an d cause rust.
 To prevent corrosion, avoi d
d amp cellars, sta bles ( because
of the presence of ammonia)
an d areas where stron g chemi-
cals are store d.
Lon g term stora ge
Before storing the vehicle long term (60
days or more): 1. Make all necessary repairs and perform any outstanding mainte-
nance.
2. Follow all instructions in the Care Section of this chapter.
3. Fill up the fuel tank and add fuel stabilizer according to product in-
structions.
4. Run the engine for 5 minutes to distribute treated fuel through the
fuel system.
5. For vehicles with a fuel cock: Turn the fuel cock lever to the off posi-
tion. 6. For vehicles with a carburetor: To
prevent fuel deposits from build-
ing up, drain the fuel in the carbu-
retor float chamber into a clean
container. Retighten the drain bolt
and pour the fuel back into the fuel
tank.
7. Use a quality engine fogging oil according to product instructions.
If engine fogging oil is not avail-
able, perform the following steps
for each cylinder:a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several times with the starter or kick-
starter. (This will coat the cylin-
der wall with oil.) WARNING!
To prevent d amage or injury
from sparkin g, make sure to
g roun d the spark plu g elec-
tro des while turnin g the en-
g ine over.
[EWA10952]
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap.
8. Lubricate all control cables, piv- ots, levers and pedals, as well as
the sidestand and centerstand (if
equipped).
9. Check and correct the tire air pressure, and then lift the vehicle
so that all wheels are off the
UB4B81E0.book Page 4 Friday, March 1, 2019 2:54 PM

11-1
11
Index
A
Air filter element, cleaning .................... 7-10
B
Brake and clutch levers, checking and
lubricating ........................................... 7-24
Brake fluid, changing ............................ 7-21
Brake fluid level, checking .................... 7-20
Brake lever .............................................. 4-2
Brake lever free play, checking............. 7-18
Brake pedal............................................. 4-3
Brake pedal, checking and lubricating ........................................... 7-25
C
Cables, checking and lubricating ......... 7-23
Carburetor, adjusting ............................ 7-12
Care ........................................................ 8-1
Clutch lever ............................................. 4-1
Clutch lever free play, adjusting ........... 7-17
Coolant ................................................... 7-8
D
Drive chain, cleaning and lubricating .... 7-23
Drive chain slack................................... 7-21
E
Engine break-in....................................... 6-1
Engine idling speed .............................. 7-13
Engine overheating ............................... 7-33
Engine serial number ............................ 10-1
Engine, starting a warm .......................... 6-3
Engine stop switch ................................. 4-1
F
Front and rear brake pads, checking.... 7-19
Front fork, adjusting................................ 4-9
Front fork, bleeding .............................. 4-11
Front fork, checking .............................. 7-26
Fuel ......................................................... 4-4
Fuel cock ................................................ 4-7
Fuel tank breather hose .......................... 4-6
Fuel tank cap .......................................... 4-3
H
Handlebar switch .................................... 4-1
I
Identification numbers .......................... 10-1
K
Kickstarter............................................... 4-8
L
Labels, location....................................... 1-1
M
Matte color, caution ................................ 8-1
P
Parking .................................................... 6-5 Part locations ......................................... 3-1
Periodic maintenance and lubrication
chart ..................................................... 7-2
R
Rear suspension, lubricating ................ 7-25
S
Safety information .................................. 2-1
Seat ........................................................ 4-8
Shifting ................................................... 6-4
Shift pedal .............................................. 4-2
Shift pedal, checking ............................ 7-18
Shock absorber assembly, adjusting ... 4-12
Sidestand ............................................. 4-15
Spark plug, checking ............................. 7-6
Specifications ......................................... 9-1
Starter (choke) knob ............................... 4-7
Starting and warming up a cold engine .................................................. 6-3
Steering, checking................................ 7-27
Storage ................................................... 8-4
Supporting the motorcycle................... 7-28
Swingarm pivots, lubricating ................ 7-26
T
Throttle grip and cable, checking and lubricating .......................................... 7-24
Throttle grip free play, adjusting........... 7-13
Tires ...................................................... 7-14
Transmission oil ..................................... 7-7
Troubleshooting ................................... 7-31
Troubleshooting chart .......................... 7-32
V
Vehicle identification number ............... 10-1
W
Wheel bearings, checking .................... 7-27
Wheel (front) ......................................... 7-28
Wheel (rear) .......................................... 7-29
Wheels .................................................. 7-16
Y
YPVS system ........................................ 4-16
UB4B81E0.book Page 1 Friday, March 1, 2019 2:54 PM