2019 YAMAHA YZ85 spark

Periodic maintenance an d a djustment
7-7
7 To install the spark plu
g
1. Clean the surface of the spark plug gasket and its mating surfa-
ce, 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.
Tightenin g 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
7-31
7
EAU25872
Trou bleshootin g
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWA15142
When checkin g the fuel system, do
not smoke, an d make sure there are
no open flames or sparks in the ar-
ea, inclu din g pilot lig hts from water
heaters or furnaces. Gasoline or
g asoline vapors can i gnite or ex-
plod e, causin g severe injury or prop-
erty damag e.
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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
halfw ay and operate
the kickstarter.Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug.
2. IgnitionW et
Dry
There is compression.
There is no
compression.
The engine does not start.
Ha ve a Yamaha dealer check the v ehicle.
Have a Yamaha dealer check the v ehicle.
The engine does not
start.
Check the
compression.Have a Yamaha
dealer check the
v ehicle.
Remo ve the spark
plug and check
the electrodes.
Operate the
kickstarter.
Check the fuel le vel
in the fuel tank.
3. Compression
UB4B80E0.book Page 32 Tuesday, March 27, 2018 1:39 PM

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
8-3
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, YZ85K)
1895 mm (74.6 in) (YZ85LW, YZ85LWK)
Overall width: 760 mm (29.9 in)
Overall height:
1145 mm (45.1 in) (YZ85, YZ85K)
1175 mm (46.3 in) (YZ85LW, YZ85LWK)
Seat height:
840 mm (33.1 in) (YZ85, YZ85K)
870 mm (34.3 in) (YZ85LW, YZ85LWK)
Wheelbase:
1255 mm (49.4 in) (YZ85, YZ85K)
1285 mm (50.6 in) (YZ85LW, YZ85LWK)
Ground clearance: 330 mm (12.99 in) (YZ85, YZ85K)
360 mm (14.17 in) (YZ85LW, YZ85LWK)
Wei ght:
Curb weight:
73 kg (161 lb) (YZ85, YZ85K)
75 kg (165 lb) (YZ85LW, YZ85LWK)
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:
8.2–9.6 : 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): 0.55 L (0.58 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: 3.286 (46/14) (YZ85, YZ85K)
3.643 (51/14) (YZ85LW, YZ85LWK)
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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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....................................... 6-3
Engine idling speed .............................. 7-13
Engine serial number ............................ 10-1
Engine, starting a warm .......................... 6-2
Engine stop switch ................................. 4-1
F
Front and rear brake pads, checking.... 7-19
Front fork, adjusting................................ 4-8
Front fork, bleeding .............................. 4-10
Front fork, checking .............................. 7-26
Fuel ......................................................... 4-4
Fuel cock ................................................ 4-6
Fuel tank breather hose .......................... 4-6
Fuel tank cap .......................................... 4-3
H
Handlebar switch .................................... 4-1
I
Identification numbers .......................... 10-1
K
Kickstarter............................................... 4-7
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 ................................................... 6-2
Shift pedal .............................................. 4-2
Shift pedal, checking ............................ 7-18
Shock absorber assembly, adjusting ... 4-11
Sidestand ............................................. 4-14
Spark plug, checking ............................. 7-6
Specifications ......................................... 9-1
Starter (choke) knob ............................... 4-7
Starting and warming up a cold engine .................................................. 6-1
Steering, checking................................ 7-27
Storage ................................................... 8-3
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 charts ........................ 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 ........................................ 4-15
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