engine YAMAHA YZ85 2018 Owner's Manual

Periodic maintenance an d a djustment
7-12
7
10. Install the air filter case cover in the original position as shown.
11. Install the seat.
EAU42111
A djustin g the car buretor
The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
carburetor adjustments should be left
to a Yamaha dealer, who has the nec-
essary professional knowledge and ex-
perience. The adjustment described in
the following section, however, may be
serviced by the owner as part of rou-
tine maintenance.
NOTICE
ECA10551
The car buretor has b een set and ex-
tensively teste d at the Yamaha fac-
tory. Chan gin g these settin gs
without sufficient technical knowl-
e dge may result in poor perfor-
mance of or d amage to the en gine.
1. Air filter element
2. Projection
1. Washer
1
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Periodic maintenance an d a djustment
7-13
7
EAU44391
A djustin g the en gine i dlin 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 g rip free play:
3.0–5.0 mm (0.12–0.20 in)
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Periodic maintenance an d a djustment
7-32
7
EAU66360
Trou bleshootin g charts
Startin g pro blems or poor en gine performance
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 operate
the kickstarter.Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug.
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.
Operate the
kickstarter.
Check the fuel level
in the fuel tank.
3. Compression
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Periodic maintenance an d a djustment
7-33
7 En
gine overheatin g
WARNING
EWAT1041
Do not remove the ra diator cap when the en gine 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 eng ine has cooled.
 Place a thick ra g, like a towel, over the ra diator cap, an d then slowly ro-
tate the cap counterclockwise to the detent to allow any resi dual pres-
sure to escape. When the hissin g soun d has stopped , press down 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.
Add coolant.
(See TIP.)
The coolant level is
OK.
Check the coolant
level in the radiator.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.
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Motorcycle care and stora ge
8-1
8
EAU37834
Matte color caution
NOTICE
ECA15193
Some mo dels are equipped with
matte colored finished parts. Be
sure to consult a Yamaha dealer for
a d vice on what pro ducts to use be-
fore cleanin g the vehicle. Usin g a
b rush, harsh chemical prod ucts or
cleanin g compoun ds when cleanin g
these parts will scratch or damag e
their surface. Wax also shoul d not
b e applie d to any matte colored fin-
ishe d parts.
EAU41359
Care
While the open design of a motorcycle
reveals the attractiveness of the tech-
nology, it also makes it more vulnera-
ble. Rust and corrosion can develop
even if high-quality components are
used. A rusty exhaust pipe may go un-
noticed on a car, however, it detracts
from the overall appearance of a mo-
torcycle. Frequent and proper care
does not only comply with the terms of
the warranty, but it will also keep your
motorcycle looking good, extend its
life and optimize its performance.
Before cleanin g
1. Cover the muffler outlet with a plastic bag after the engine has
cooled down.
2. Make sure that all caps and cov- ers as well as all electrical cou-
plers and connectors, including
the spark plug cap, are tightly in-
stalled.
3. Remove extremely stubborn dirt, like oil burnt onto the crankcase,
with a degreasing agent and a
brush, but never apply such prod-
ucts onto seals, gaskets, sprock-
ets, the drive chain and wheel
axles. Always rinse the dirt and
degreaser off with water.
Cleanin g
NOTICE
ECA17692
Avoi d using strong aci dic wheel
cleaners, especially on spoked
wheels. If such pro ducts are
use d on har d-to-remove dirt, do
not leave the cleaner on the af-
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Motorcycle care and stora ge
8-2
8 fected
area any lon ger than in-
structe d. Also, thorou ghly rinse
the area off with water, imme di-
ately dry it, an d then apply a cor-
rosion protection spray.
 Improper cleanin g can d amage
plastic parts (such as cowlin gs,
panels, etc.) an d the mufflers.
Use only a soft, clean cloth or
spon ge with water to clean
plastic. However, if the plastic
parts cannot be thorou ghly
cleaned with water, dilute d mil d
d eter gent with water may b e
use d. Be sure to rinse off any
d eter gent resi due using plenty
of water, as it is harmful to plas-
tic parts.
 Do not use any harsh chemical
prod ucts on plastic parts. Be
sure to avoi d using cloths or
spon ges which have been in
contact with stron g or a brasive
cleanin g prod ucts, solvent or
thinner, fuel (g asoline), rust re-
movers or inhi bitors, brake flui
d,
an

tifreeze or electrolyte.
 Do not use hi gh-pressure wash-
ers or steam-jet cleaners since
they cause water seepa ge an d
d eterioration in the followin g ar-
eas: seals (of wheel an d swin g-
arm bearin gs, fork an d b rakes),
electric components (couplers,
connectors, an d switches),
b reather hoses an d vents.
After normal use
Remove dirt with warm water, a mild
detergent, and a soft, clean sponge,
and then rinse thoroughly with clean
water. Use a toothbrush or bottlebrush
for hard-to-reach areas. Stubborn dirt and insects will come off more easily if
the area is covered with a wet cloth for
a few minutes before cleaning.
After riding in the rain or near the sea
Since sea salt is extremely corrosive,
carry out the following steps after each
ride in the rain or near the sea.
1. Clean the motorcycle with cold water and a mild detergent, after
the engine has cooled down.
NOTICE: Do not use warm wa-
ter since it increases the corro-
sive action of the salt.
[ECA10792]
2. Apply a corrosion protection spray on all metal, including chrome-
and nickel-plated, surfaces to pre-
vent corrosion.
After cleaning 1. Dry the motorcycle with a chamois or an absorbing cloth.
2. Immediately dry the drive chain and lubricate it to prevent it from
rusting.
3. Use a chrome polish to shine chrome, aluminum and stainless-
steel parts, including the exhaust
system.
4. To prevent corrosion, it is recom- mended to apply a corrosion pro-
tection spray on all metal,
including chrome- and nickel-plat-
ed, surfaces.
5. Use spray oil as a universal clean- er to remove any remaining dirt.
6. Touch up minor paint damage caused by stones, etc.
7. Wax all painted surfaces.
8. Let the motorcycle dry completely before storing or covering it.
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Motorcycle care and stora ge
8-3
8
WARNING
EWA11132
Contaminants on the brakes or tires
can cause loss of control.  Make sure that there is no oil or
wax on the brakes or tires.
 If necessary, clean the brake
d iscs an d b rake linin gs with a
re gular brake disc cleaner or
acetone, an d wash the tires with
warm water an d a mil d d eter-
g ent. Before ri din g at hi gher
speed s, test the motorcycle’s
b rakin g performance an d cor-
nering b ehavior.
NOTICE
ECA10801
 Apply spray oil an d wax spar-
in gly an d make sure to wipe off
any excess.
 Never apply oil or wax to any
rubber an d plastic parts, but
treat them with a suitab le care
prod uct.
 Avoi d using abrasive polishin g
compoun ds as they will wear
away the paint.
TIP
Consult a Yamaha dealer for advice on
what products to use.
EAU41515
Stora ge
Short-term
Always store your motorcycle in a cool,
dry place and, if necessary, protect it
against dust with a porous cover. Be
sure the engine and the exhaust sys-
tem are cool before covering the mo-
torcycle.
NOTICE
ECA10811
 Storin g the motorcycle in a
poorly ventilate d room or cover-
in g it with a tarp, while it is still
wet, will allow water an d humi d-
ity to seep in an d cause rust.
 To prevent corrosion, avoi d
d amp cellars, sta bles (b ecause
of the presence of ammonia)
an d areas where stron g chemi-
cals are stored .
Long-term
Before storing your motorcycle for sev-
eral months: 1. Follow all the instructions in the “Care” section of this chapter.
2. For motorcycles equipped with a fuel cock that has an “OFF” posi-
tion: Turn the fuel cock lever to
“OFF”.
3. Drain the fuel tank and fuel lines, and the carburetor float chamber
by loosening the drain bolt; this
will prevent fuel deposits from
building up.
4. Perform the following steps to protect the cylinder, piston rings,
etc. from corrosion.a. Remove the spark plug cap and spark plug.
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Motorcycle care and stora ge
8-4
8 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. (This will
coat the cylinder wall with oil.)
e. Remove the spark plug cap from the spark plug, and then
install the spark plug and the
spark plug cap. WARNING! To
prevent damag e 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]
5. Lubricate all control cables and
the pivoting points of all levers and
brake pedal.
6. Check and, if necessary, correct the tire air pressure, and then lift
the motorcycle so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
7. Cover the muffler outlet with a plastic bag to prevent moisture
from entering it.
TIP
Make any necessary repairs before
storing the motorcycle.
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Specifications
9-1
9
Dimensions:
Overall length:1820 mm (71.7 in) (YZ85, YZ85J)
1900 mm (74.8 in) (YZ85LW, YZ85LWJ)
Overall width: 760 mm (29.9 in)
Overall height:
1125 mm (44.3 in) (YZ85, YZ85J)
1155 mm (45.5 in) (YZ85LW, YZ85LWJ)
Seat height:
840 mm (33.1 in) (YZ85, YZ85J)
875 mm (34.4 in) (YZ85LW, YZ85LWJ)
Wheelbase:
1255 mm (49.4 in) (YZ85, YZ85J)
1285 mm (50.6 in) (YZ85LW, YZ85LWJ)
Ground clearance: 330 mm (12.99 in) (YZ85, YZ85J)
360 mm (14.17 in) (YZ85LW, YZ85LWJ)
Wei ght:
Curb weight:
71 kg (157 lb) (YZ85, YZ85J)
73 kg (161 lb) (YZ85LW, YZ85LWJ)
Engine:
Combustion cycle:
2-stroke
Cooling system: Liquid cooled
Number of cylinders:
Single cylinder
Displacement: 85 cm³
Bore × stroke:
47.5 × 47.8 mm (1.87 × 1.88 in)
Compression ratio:
8.1 : 1
Starting system: Kickstarter
Lubrication system: Premix lubrication
Engine oil:
Engine oil:
YAMALUBE 2R
Recommended brand: YAMALUBE
Transmission oil:
Type:Motor oil SAE 10W-30 type SE or higher or
Gear oil SAE 85W GL-3
Quantity: 0.50 L (0.53 US qt, 0.44 Imp.qt)
Coolant quantity:
Radiator (including all routes): 0.54 L (0.57 US qt, 0.48 Imp.qt)
Air filter:
Air filter element:Wet element
Fuel:
Recommended fuel:
Premium unleaded gasoline (Gasohol [E10]
acceptable)
Fuel tank capacity:
5.0 L (1.3 US gal, 1.1 Imp.gal)
Car buretor:
Type × quantity:
PWK28 × 1
Spark plu g(s):
Manufacturer/model:
NGK/BR10EG
Spark plug gap: 0.5–0.6 mm (0.020–0.024 in)
Clutch:
Clutch type:
Wet, multiple-disc
Drivetrain:
Primary reduction ratio:3.611 (65/18)
Final drive:
Chain
Secondary reduction ratio: 3.429 (48/14) (YZ85, YZ85J)
3.714 (52/14) (YZ85LW, YZ85LWJ)
Transmission type: Constant mesh 6-speed
Gear ratio: 1st:2.455 (27/11)
2nd: 1.882 (32/17)
3rd:
1.529 (26/17)
4th: 1.294 (22/17)
5th: 1.130 (26/23)
6th:
1.000 (25/25)
Chassis:
Frame type: Semi double cradle
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Consumer information
10-1
10
EAU26365
Id entification num bers
Record the vehicle identification num-
ber and the engine serial number in the
spaces provided below for assistance
when ordering spare parts from a
Yamaha dealer or for reference in case the vehicle is stolen.
VEHICLE IDENTIFICATION NUMBER:
ENGINE SERIAL NUMBER:
EAU26401Vehicle i dentification num ber
The vehicle identification number is
stamped into the steering head pipe.
Record this number in the space pro-
vided.
TIP
The vehicle identification number is
used to identify your motorcycle and
may be used to register your motorcy-
cle with the licensing authority in your
area.
EAU26442En gine serial num ber
The engine serial number is stamped
into the crankcase.
1. Vehicle identification number
1. Engine serial number
1
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