2022 YAMAHA YFM90R Owners Manual

9-26
9
2. Loosen the rear brake lever free play adjust- ing nut. 3. Loosen the locknut.
1. Bolt
1. Nut
1
1
1. Rear brake lever free play adjusting nut
1. Drive chain slack adjusting nut
2. Locknut
1
1
2
(a)
(b)
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9-27
94. To tighten the drive chain, turn the drive chain
slack adjusting nut in direction (a). To loosen
the drive chain, turn the adjusting nut in direc-
tion (b) and push the rear wheels forward.
NOTICE: Improper drive chain slack will
overload the engine as well as other vital
parts of the ATV and can lead to drive
chain slippage or breakage. To prevent
this from occurring, keep the drive chain
slack within the specified limits.
[ECB00543]
5. Tighten the locknut, and then the bolts and nuts to their specified torques.
6. Adjust the rear brake lever free play. (See page 9-24.)
EBU24886Lubricating the drive chainThe drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
chart, otherwise it will quickly wear out, especially
when riding in dusty or wet areas. Service the
drive chain as follows.NOTICEECB00562The drive chain must be lubricated after wash-
ing the ATV or riding in the rain or wet areas.
Tightening torques:Locknut:22 N·m (2.2 kgf·m, 16 lb·ft)
Bolt: 45 N·m (4.5 kgf·m, 33 lb·ft)
Nut: 54 N·m (5.4 kgf·m, 40 lb·ft)
1. O-ring
1
1
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9-28
9
1. Clean the drive chain with a drive chain clean-
er and a small soft brush. NOTICE: To pre-
vent damaging the O-rings, do not clean
the drive chain with steam cleaners, high-
pressure washers or inappropriate sol-
vents.
[ECB00572]
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a special O-ring chain lubricant. NOTICE: Do
not use engine oil or any other lubricants
for the drive chain, as they may contain
substances that could damage the O-
rings.
[ECB00582]
EBU24905
Checking and lubricating the cablesThe operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING
EWB02582 Inspect cables frequently and replace if
damaged. Corrosion can result when the ca-
ble sheaths become damaged, and cables
can also become frayed or kinked, which
could restrict the operation of controls and
lead to an accident or injury.
 Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or
do not work smoothly, you could be unable
to control the ATV, which could lead to an
accident or collision. EBU28703Checking and lubricating the front and
rear brake leversThe operation of the front and rear brake levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Recommended lubricant: Yamaha cable lubricant or other suitable cable lubricantRecommended lubricant: Lithium-soap-based grease
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9-29
9Front brake lever
Rear brake lever
EBU24965Checking the wheel hub bearingsThe front and rear wheel hub bearings must be
checked at the intervals specified in the periodic
maintenance chart. If there is play in a wheel hub
or if a wheel does not turn smoothly, have a
Yamaha dealer check the wheel hub bearings.EBU36392Lubricating the front arm pivotsThe front arm pivots must be lubricated at the in-
tervals specified in the periodic maintenance
chart.Recommended lubricant: Lithium-soap-based grease
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9-30
9
TIPFor parts equipped with a grease nipple, use a
grease gun. EBU28826Lubricating the front knuckle pivotsThe front knuckle pivots must be lubricated at the
intervals specified in the periodic maintenance
chart.
TIPFor parts equipped with a grease nipple, use a
grease gun. EBU25096Lubricating the steering shaftThe steering shaft must be lubricated by a
Yamaha dealer at the intervals specified in the pe- riodic maintenance chart.
1. Grease nippleRecommended lubricant: Lithium-soap-based grease
1
1
1. Grease nippleRecommended lubricant:Lithium-soap-based grease
1
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9-31
9
TIPFor parts equipped with a grease nipple, use a
grease gun. EBU34022BatteryThis model is equipped with a 12-volt VRLA
(valve-regulated lead-acid) battery. There is no
need to check the electrolyte or to add distilled
water. However, the battery lead connections
need to be checked and tightened, and the bat-
tery terminals cleaned if corroded. If the battery
seems to have discharged, recharge it as soon as
possible.TIPWear gloves and eye protection in a ventilated
area away from sparks and open flames. Wash
hands after handling.
 It is recommended to have the battery serviced
by a Yamaha dealer.
WARNING
EWB02161Battery electrolyte is poisonous and danger-
ous, as it contains sulfuric acid, which can
cause severe burns. Avoid contact with skin,
eyes or clothing. Always shield your eyes when
working near batteries.
Antidote:
EXTERNAL: Flush with water.
INTERNAL: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten egg
or vegetable oil. Call a physician immediately.
EYES: Flush with water for 15 minutes and get
prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes or other sources of
ignition away. Ventilate when charging or using
in an enclosed space.
KEEP OUT OF REACH OF CHILDREN. To remove the battery
1. Remove the seat. (See page 5-13.)
2. Unhook the battery band.
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9-32
9
3. Disconnect the negative battery lead first,
then the positive battery lead by removing
their bolt. NOTICE: When removing the bat-
tery, the main switch must be off, and the
negative lead must be disconnected be-
fore the positive lead.
[ECB01002]
4. Pull the battery out of its compartment.
NOTICEECB00622Never attempt to open the battery or remove
the battery cell seals, as this would permanent-
ly damage the battery. To charge the battery
 Confirm the recommended charging rate as
specified on the battery itself.
 Select a suitable charger and follow the manu-
facturer’s instructions.NOTICEECB00933To charge a VRLA (valve-regulated lead-acid)
battery, a special battery charger is required.
Using a conventional battery charger will dam-
age the battery. To store the battery
If the ATV will not be used for more than one
month, remove the battery, fully charge it, and
then place it in a cool, dry place.
 If the battery will be stored for more than two
months, check it at least once a month and fully
charge it if necessary.
1. Positive battery lead (red)
2. Negative battery lead (black)
3. Battery
4. Battery band
3
4
2
1
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9
NOTICEECB00942Always keep the battery charged. Storing the
battery in a discharged state for an extended
period of time will cause permanent battery
damage.
 Do not store the battery in an excessively
cold or warm place [below freezing or above
30 °C (90 °F)]. To install the battery
1. Place the battery in its compartment.
2. Connect the positive battery lead first, then connect the negative battery lead by installing
their bolt. NOTICE: When installing the bat-
tery, the main switch must be off, and the
positive lead must be connected before
the negative lead.
[ECB01111]
3. Hook the battery band.
4. Install the seat. (See page 5-13.)TIP Make sure the positive and negative battery
leads are installed as shown.
 Fully charge the battery before installing it. 1. Positive battery lead (red)
2. Negative battery lead (black)
2
1
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