2019 YAMAHA YZ85 oil type

Instrument and control functions
4-4
4
EAU41837
Fuel
This motorcycle has been designed to
use a premixed fuel of gasoline and 2-
stroke engine oil. Always mix the gaso-
line and oil in a clean container before
filling the fuel tank.
NOTICE
ECA15602
Always use fresh g asoline, and fill
the fuel tank with a fresh mix just be-
fore ri din g. Do not use premixe d fuel
that is more than a few hours ol d.
Mixin g g asoline an d 2-stroke en gine
oil
Pour 2-stroke engine oil into a clean
container, and then add gasoline. To
mix the fuel thoroughly, shake the con-
tainer from side to side.
NOTICE
ECA15591
Use only unlea ded g asoline. The use
of lead ed 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.
Your Yamaha engine has been de-
signed to use premium unleaded gas-
oline with a pump octane number
[(R+M)/2] of 91 or higher, or a research
octane number of 95 or higher. If
knocking (or pinging) occurs, use a
gasoline of a different brand.
If the recommended 2-stroke engine
oil is not available, use an equivalent
oil.
Gasohol
There are two types of gasohol: gaso-
hol containing ethanol and that con-
taining methanol. Gasohol containing
ethanol can be used if ethanol content
does not exceed 10% (E10). Gasohol
containing methanol is not recom-
mended by Yamaha because it can
cause damage to the fuel system or
vehicle performance problems.
NOTICE
ECA15552
Never mix two b rands of 2-stroke
en gine oil in the same b atch. Always
use the same type of oil to ensure
maximum en gine performance.
Shoul d it b e necessary to use a dif-
ferent oil bran d, b e sure to drain the
fuel tank an d the car buretor float
cham ber of the ol d premixe d fuel
prior to fillin g with the new type.1. 2-stroke engine oil
2. Gasoline
3. Container
Recommen ded fuel:
Premium unleaded gasoline (Gaso-
hol [E10] acceptable)
Recommen ded 2-stroke en gine oil:
YA M A L U B E 2 R
Fuel tank capacity: 5.0 L (1.3 US gal, 1.1 Imp.gal)
Mixin g ratios ( gasoline to oil):
Break-in period: 15:1
After break-in: 30:1
UB4B80E0.book Page 4 Tuesday, March 27, 2018 1:39 PM

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), do
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 surfa- ce 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 ghtening 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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Periodic maintenance an d a djustment
7-11
7 4. Remove the sponge material from
the air filter element frame.
5. Clean the sponge material with solvent, and then squeeze the re-
maining solvent out. 6. Apply oil of the recommended
type to the entire surface of the
sponge material, and then
squeeze the excess oil out.
TIP
The sponge material should be wet but
not dripping.
7. Pull the sponge material over theair filter element frame.
8. Insert the air filter element into the air filter case with the projection
facing upward, and then install the
wing bolt and its washer.
NOTICE: Make sure that the air
filter element is properly seate d
in the air filter case. The en gine
shoul d never b e operated with-
out the air filter element in-
stalle d, otherwise the piston(s)
an d/or cylin der(s) may become
excessively worn.
[ECA10482]
NOTICE: Be sure to install the
washer with its curve d si de fac-
in g outwar d as shown.
[ECA16692]
1. Wing bolt
2. Washer
3. Air filter element
1. Sponge material
2. Air filter element frame
1
2
Recommended oil:
Yamaha foam air filter oil or other
quality foam air filter oil
1. Air filter element
2. Projection
UB4B80E0.book Page 11 Tuesday, March 27, 2018 1:39 PM

Periodic maintenance an d a djustment
7-20
7
EAU22583
Checkin g the brake flui d level
Before riding, check that the brake fluid
is above the minimum level mark.
Check the brake fluid level with the res-
ervoir in an upright position. Replenish
the brake fluid if necessary.
NOTICE
ECA17641
Brake flui d may damag e painte d
surfaces or plastic parts. Always
clean up spille d flui d imme diately.
Front brake
Rear brake
As the brake pads wear, it is normal for
the brake fluid level to gradually go
down. 
A low brake fluid level may indi-
cate worn brake pads or brake
system leakage; therefore, be sure
to check the brake pads for wear
and the brake system for leakage.
 If the brake fluid level goes down
suddenly, have a Yamaha dealer
check the cause before further rid-
ing.
WARNING
EWA15991
Improper maintenance can result in
loss of b raking a bility. O bserve
these precautions:  Insufficient brake flui d may al-
low air to enter the brake sys-
tem, re ducin g brakin g
performance.
 Clean the filler cap before re-
moving . Use only DOT 4 b rake
flui d from a seale d container.
 Use only the specifie d b rake flu-
i d ; otherwise, the ru bber seals
may deteriorate, causin g leak-
a g e.
 Refill with the same type of
brake flui d. A ddin g a brake flui d
other than DOT 4 may result in a
harmful chemical reaction.
 Be careful that water d oes not
enter the brake flui d reservoir
when refillin g. Water will si gnifi-
cantly lower the b oiling point of
the flui d an d may result in vapor
lock.
Specified b rake flui d:
DOT 4
1. Minimum level mark
1. Minimum level mark
1
UB4B80E0.book Page 20 Tuesday, March 27, 2018 1:39 PM

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
UB4B80E0.book Page 1 Tuesday, March 27, 2018 1:39 PM

Specifications
9-2
9
Caster angle:26.0 ° (YZ85LW, YZ85LWK)
26.3 ° (YZ85, YZ85K)
Trail: 88 mm (3.5 in) (YZ85, YZ85K)
99 mm (3.9 in) (YZ85LW, YZ85LWK)
Front tire:
Type:With tube
Size:
70/100-17 40M (YZ85, YZ85K)
70/100-19 42M (YZ85LW, YZ85LWK)
Manufacturer/model:
DUNLOP/MX3SF
Rear tire:
Type: With tube
Size: 90/100-14 49M (YZ85, YZ85K)
90/100-16 52M (YZ85LW, YZ85LWK)
Manufacturer/model: DUNLOP/MX3S
Tire air pressure (measure d on col d
tires):
Front:
100 kPa (1.00 kgf/cm², 15 psi)
Rear:
100 kPa (1.00 kgf/cm², 15 psi)
Front wheel:
Wheel type:Spoke wheel
Rim size:
17 x 1.40 (YZ85, YZ85K)
19 x 1.40 (YZ85LW, YZ85LWK)
Rear wheel:
Wheel type:Spoke wheel
Rim size: 14 x 1.60 (YZ85, YZ85K)
16 x 1.85 (YZ85LW, YZ85LWK)
Front brake:
Type:
Hydraulic single disc brake
Specified brake fluid: DOT 4
Rear brake:
Type:
Hydraulic single disc brake
Specified brake fluid: DOT 4
Front suspension:
Type:Telescopic fork
Spring:
Coil spring
Shock absorber: Hydraulic damper
Wheel travel: 275 mm (10.8 in)
Rear suspension:
Type:Swingarm (link suspension)
Spring: Coil spring
Shock absorber: Gas-hydraulic damper
Wheel travel:
282 mm (11.1 in) (YZ85, YZ85K)
287 mm (11.3 in) (YZ85LW, YZ85LWK)
Electrical system:
Ignition system:CDI
Charging system: CDI magneto
UB4B80E0.book Page 2 Tuesday, March 27, 2018 1:39 PM