2022 YAMAHA YZ85 cooling

For your safety – pre-operation checks
5-1
5
EAU1559B
Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always follow the inspection
and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWA11152
Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equipment d amage.
Do not operate the vehicle if you fin d any pro blem. If a pro blem cannot b e corrected b y the proce dures provi ded in
this manual, have the vehicle inspecte d b y a Yamaha dealer.Before using this vehicle, check the following points:
ITEM CHECKS PAGE
Fuel • Check fuel level in fuel tank.
• Always use a fresh mixture of gasoline and oil.
• Check fuel line for leakage.
• Check fuel tank breather hose for obstructions, cracks or damage, and check
hose connection. 4-3, 4-6
Transmission oil • Check for leakage. 7-8
Coolant • Check coolant level.
• If necessary, add recommended coolant to specified level.
• Check cooling system for leakage. 7-9
Front brake • Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic system.
• Check brake pads for wear.
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add specified brake fluid to specified level.
• Check hydraulic system for leakage. 7-18, 7-19
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Periodic maintenance an d a djustment
7-10
7
TIPThe coolant should be at the bottom of
the radiator filler neck. The level will
change with variation of engine tem-
perature.
3. If the coolant is below the correct
coolant level, add coolant, and
then install the radiator cap.
NOTICE: If coolant is not avail-
a b le, use d istilled water or soft
tap water instea d. Do not use
har d water or salt water since it
is harmful to the en gine. If water
has been used instead of cool-
ant, replace it with coolant as
soon as possi ble, otherwise the
coolin g system will not b e pro-
tected against frost an d corro-
sion. If water has b een added to
the coolant, have a Yamaha
d ealer check the antifreeze con-
tent of the coolant as soon as
possi ble, otherwise the effec-
tiveness of the coolant will be
re duce d.
[ECA10473]
EAUM1318
To change the coolant
1. Place the vehicle on a level sur- face and let the engine cool if nec-
essary.
2. Place a container under the en- gine to collect the used coolant. 3. Remove the radiator cap, and
then the coolant drain bolt and its
gasket to drain the cooling sys-
tem. WARNING! Never attempt
to remove the ra diator cap
when the en gine is hot.
[EWA10382]
1. Radiator cap
1. Correct coolant level
11
1
1. Radiator cap
1. Coolant drain bolt
2. Gasket
11
2
1
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Periodic maintenance an d a djustment
7-11
7 4. After the coolant is completely
drained, thoroughly flush the cool-
ing system with clean tap water.
5. Install the coolant drain bolt and its new gasket, and then tighten
the bolt to the specified torque.
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 min-
utes, 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.
EAU48394
Cleanin g the air filter elementThe 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 4-7.)
2. Remove the air filter element by removing the wing bolt and its
washer.
3. Remove the sponge material from the air filter element frame.
Tightenin g torque:
Coolant drain bolt: 10 N·m (1.0 kgf·m, 7.4 lb·ft)
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):0.50 L (0.53 US qt, 0.44 Imp.qt)
1. Wing bolt
2. Washer
3. Air filter element
1 1
3 32
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Periodic maintenance an d a djustment
7-31
7
EAU86420
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 be
b lown 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 ra diator cap, an d then slowly rotate the cap counterclockwise to the
d etent to allow any resi dual pressure 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.TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended cool-
ant as soon as possible.
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
UB4B83E0.book Page 31 Thursday, September 9, 2021 8:47 AM

Specifications
9-1
9
Dimensions:Overall length:1820 mm (71.7 in) (YZ85, YZ85N)
1895 mm (74.6 in) (YZ85LW, YZ85LWN)
Overall width: 760 mm (29.9 in)
Overall height:
1135 mm (44.7 in) (YZ85, YZ85N)
1175 mm (46.3 in) (YZ85LW, YZ85LWN)
Seat height:
840 mm (33.1 in) (YZ85, YZ85N)
885 mm (34.8 in) (YZ85LW, YZ85LWN)
Wheelbase:
1255 mm (49.4 in) (YZ85, YZ85N)
1285 mm (50.6 in) (YZ85LW, YZ85LWN)
Ground clearance:
320 mm (12.60 in) (YZ85, YZ85N)
360 mm (14.17 in) (YZ85LW, YZ85LWN)Wei ght:Curb weight:
73 kg (161 lb) (YZ85, YZ85N)
75 kg (165 lb) (YZ85LW, YZ85LWN)
Maximum rider weight: 62.0 kg (137 lb)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)
Starting system: Kickstarter
Engine oil:Engine oil:
YAMALUBE 2R
Recommended brand:Transmission oil:Type: Motor oil SAE 10W-40 type SG or higher
Quantity:
0.50 L (0.53 US qt, 0.44 Imp.qt)Coolant quantity:Radiator (including all routes):0.50 L (0.53 US qt, 0.44 Imp.qt)Fuel:Recommended fuel:Unleaded gasoline (E10 acceptable)
Octane number (RON): 98
Fuel tank capacity:
5.0 L (1.3 US gal, 1.1 Imp.gal)Car buretor:Type × quantity:
PWK28 × 1
Drivetrain: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)Front tire:Type:With tube
Size:
70/100-17 40M (YZ85, YZ85N)
70/100-19 42M (YZ85LW, YZ85LWN)
Manufacturer/model:
DUNLOP/MX3SFRear tire:Type: With tube
Size:
90/100-14 49M (YZ85, YZ85N)
90/100-16 52M (YZ85LW, YZ85LWN)
Manufacturer/model:
DUNLOP/MX3SFront brake:Type:
Hydraulic single disc brake
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