2009 YAMAHA YFM90R Owners Manual

4. Tighten the lower locknut.
5. While applying the front brake, turn out the up-per adjusting bolt until the upper and lower ca-
ble lengths are equal. The cable joint will
become vertical.1. Upper locknut
2. Upper adjusting bolt
3. Lower locknut
4. Lower adjusting bolt
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4
3 (a)(b)
(a)
(b)
11. Cable joint6. Tighten the upper locknut.
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WARNING
Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident.

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The rear brake pads must be checked for wear at the
intervals specified in the periodic maintenance and
lubrication chart. Each brake pad is provided with
wear indicator grooves, which allow you to check the
brake pad wear without having to disassemble the
brake. If a brake pad has worn to the point that the
wear indicator grooves have almost disappeared,
have a Yamaha dealer replace the brake pads as a
set.Checking the rear brake pads
Insufficient brake fluid may allow air to enter the brake
system, possibly causing it to become ineffective.
Before riding, check that the brake fluid is above the
minimum level mark and replenish if necessary.
A low brake fluid level may indicate worn brake pads
and/or brake system leakage. If the brake fluid level
is low, be sure to check the brake pads for wear and
the brake system for leakage.Checking the brake fluid level 1. Wear indicator groove
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1
After servicing:Make sure the brakes operate smoothly and
that the free play is correct.Make sure the brakes do not drag.
Replacement of brake components requires
professional knowledge. These proceduresshould be performed by a Yamaha dealer.

Changing the rear brake fluidChecking the rear brake lever free play
The brake lever free play must be checked at the
intervals specified in the periodic maintenance and
lubrication chart. The brake lever free play should
measure 0 – 1.5 mm (0 – 0.06 in) as shown. If
the free play is incorrect, have a Yamaha dealer
check the brake system.
1
LOWER
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Recommended brake fluid:
DOT4
1. Brake lever free play
1. Minimum level mark
Have a Yamaha dealer change the rear brake fluid
at the intervals specified in the TIP after the periodic
maintenance and lubrication chart. In addition,
have the oil seals of the master cylinders and
calipers as well as the brake hoses replaced at the
intervals listed below or whenever they are damaged
or leaking.
Oil seals: Replace every two years.Brake hoses: Replace every four years.

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Checking and lubricating the cables The 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.
Checking and lubricating the front and
rear brake levers The 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:
Engine oil
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WARNING
Operating with improperly serviced or adjust-
ed brakes could cause loss of braking ability,
which could lead to an accident.
After servicing:Make sure the brakes operate smoothly and
that the free play is correct.Make sure the brakes do not drag.Make sure the brakes are not spongy. All air
must be bled from the brake system.
Replacement of brake components requires
professional knowledge. These proceduresshould be performed by a Yamaha dealer.
WARNING
Inspect cables frequently and replace if dam-
aged. Corrosion can result when the cable
sheaths become damaged, and cables can
also become frayed or kinked, which could re-
strict the operation of controls and lead to anaccident or injury.

8-28
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Checking the wheel hub bearings The front and rear wheel hub bearings must be
checked at the intervals specified in the periodic
maintenance and lubrication 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.1. Lever pivot
BatteryT h i s m o d e l i s e q u i p p e d w i t h a V R L A ( V a l v e
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, if necessary, tightened.
Recommended lubricant:Front brake lever: Lithium-soap-based grease
N O T I C E Never attempt to remove the battery cell seals,
as this would permanently damage the battery.
1
WARNING
Battery 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.
Rear brake lever:
Silicone grease

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To charge the battery
Have a Yamaha dealer charge the battery as soon
as possible if it seems to have discharged. Keep in
mind that the battery tends to discharge more quicklyif the ATV is equipped with optional electrical
accessories. To store the battery
1. 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.
2. If the battery will be stored for more than two months, check it at least once a month and fully
charge it if necessary.
To install the battery
TIPBe sure the battery is fully charged. 1. Place the battery in its compartment.
2. Make sure to properly connect the battery leads to the battery terminals.
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1. Battery
2. Negative lead
3. Positive lead
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3
EYES: Flush with water for 15 minutes and get
prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes or other sources of ig-
nition away. Ventilate when charging or using
in an enclosed space.KEEP OUT OF REACH OF CHILDREN.

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1. Turn the key to “OFF” and turn off all electricalcircuits.N O T I C E To prevent accidental short-circuiting, turn off
the main switch when checking or replacing afuse.
2. Remove the blown fuse, and then install a new fuse of the specified amperage.
Specified fuse: 10 A
The fuse holder is located under the seat.
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(See page 4-9.)
If the fuse is blown, replace it as follows.
1. Fuse
2. Spare fuseN O T I C EAlways keep the battery charged. Storing a
discharged battery can cause permanent
battery damage.To charge a VRLA (Valve Regulated Lead Acid)
battery, a special (constant-voltage) battery
charger is required. Using a conventional
battery charger will damage the battery. If you
do not have access to a constant-voltage
battery charger, have a Yamaha dealer charge
your battery.
1
2
Replacing the fuse
WARNING
Always use a fuse of the specified rating, and
never use a substitute object in place of the
proper fuse. An improper fuse or a substitute
object can cause damage to the electrical sys-tem, which could lead to a fire.

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3. Turn the key to “ON” and turn on the electricalcircuits to check if the devices operate.
4. If the fuse immediately blows again, have a Yamaha dealer check the electrical system.
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