2007 YAMAHA YFZ450 Owners Manual

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7. To increase the clutch lever free play, turn the
adjusting nut at the crankcase in direction (a),
and to decrease it, turn the nut in direction (b).
8. Tighten the locknut at the crankcase and the
clutch lever.
NOTE:

If the specified free play cannot be obtained as de-
scribed above or if the clutch does not operate cor-
rectly, have a Yamaha dealer check the internal
clutch mechanism.
EBU26860
Drive chain slack
The drive chain slack should be checked before
each ride and adjusted if necessary.
To check the drive chain slack
1. Place the ATV on a level surface.
NOTE:

When checking and adjusting the drive chain
slack, there should be no weight on the ATV and
all tires must be touching the ground.
2. Move the ATV back and forth to locate the
tightest portion of the drive chain, and then
measure the drive chain slack as shown.
1. Locknut
2. Clutch lever free play adjusting nut (crankcase)
(a)
(b)
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1

Drive chain slack:
25.0–35.0 mm (0.98–1.38 in)

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3. If the drive chain slack is incorrect, adjust it as
follows.
To adjust the drive chain slack
1. Loosen the rear axle pinch bolts.
2. Insert a rod of a diameter of 8 mm and a
length of 10 cm into one of the holes in the
drive chain tensioner as shown.NOTE:

A rod can be obtained at a Yamaha dealer to make
this adjustment.
3. Shift the transmission into neutral.
4. To tighten the drive chain, push the ATV back-
ward. To loosen the drive chain, push the ATV
forward.
1. Drive chain slack
1

1. Rear wheel axle pinch bolt
2. Rod
3. Drive chain tensioner
4. Hole
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CAUTION:

ECB00541
Improper drive chain slack will overload the en-
gine 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.
5. Pull the rod out, and then tighten the rear axle
pinch bolts to the specified torque in the order
shown.
EBU24880
Lubricating the drive chain
The drive chain must be cleaned and lubricated at
the intervals specified in the periodic maintenance
and lubrication chart, otherwise it will quickly wear
out, especially when riding in dusty or wet areas.
Service the drive chain as follows.
CAUTION:

ECB00560
The drive chain must be lubricated after wash-
ing the ATV or riding in the rain.
1. Clean the drive chain with kerosene and a Tightening torque:
Rear axle pinch bolt:
21 Nm (2.1 m·kgf, 15.2 ft·lbf)
3124

1. O-rings
1

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small soft brush.
CAUTION:

ECB00570
To prevent damaging the O-rings, do not clean
the drive chain with steam cleaners, high-pres-
sure washers or inappropriate solvents.
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a
special O-ring chain lubricant.
CAUTION:

ECB00580
Do not use engine oil or any other lubricants
for the drive chain, as they may contain sub-
stances that could damage the O-rings.
EBU24900
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.
WARNING

EWB02130
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 an
accident or injury.
EBU24920
Checking and lubricating the brake and
clutch levers
The operation of the brake and clutch levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Recommended lubricant:
Engine oil
Recommended lubricant:
Lithium-soap-based grease (all-purpose
grease)

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Brake lever
Clutch lever

EBU24930
Checking and lubricating the brake and
shift pedals
The operation of the brake and shift pedals should
be checked before each ride, and the pedal pivots
should be lubricated if necessary.
Brake pedal
EBU24961
Checking the wheel bearings
The front and rear wheel bearings must be
Recommended lubricant:
Lithium-soap-based grease (all-purpose
grease)

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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 bearings.
EBU24992
Lubricating the swingarm pivots
The swingarm pivots must be lubricated at the in-
tervals specified in the periodic maintenance and
lubrication chart.
EBU25030
Lubricating the upper and lower arm
pivots
The upper and lower arm pivots must be lubricated
at the intervals specified in the periodic mainte-
nance and lubrication chart.
Lubricate the pivoting points using a grease gun.
Left side
Recommended lubricant:
Lithium-soap-based grease
Recommended lubricant:
Lithium-soap-based grease
1. Upper grease nipple
2. Lower grease nipple
21

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Right side

EBU25222
Battery
This model is equipped with a sealed-type (MF)
battery, which does not require any maintenance.
There is no need to check the electrolyte or to add
distilled water. Check and, if necessary, tighten the
battery lead connections.
CAUTION:

ECB00620
Never attempt to remove the battery cell seals,
as this would permanently damage the battery.WARNING
EWB02160
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.
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.
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
quickly if the ATV is equipped with optional electri-
cal accessories.
1. Upper grease nipple
2. Lower grease nipple
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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 ful-
ly charge it if necessary.
To install the battery
NOTE:

Be 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.
CAUTION:

ECB00630

Always keep the battery charged. Storing a
discharged battery can cause permanent
battery damage.

To charge a sealed-type (MF) battery, a spe-
cial constant-voltage battery charger is re-
quired. Using a conventional battery charger
will damage the battery. If you do not have
access to a constant-voltage battery charg-
er, have a Yamaha dealer charge your bat-
tery.
EBU25262
Replacing the fuse
The fuse holder is located on the right side of the
ATV.
If the fuse is blown, replace it as follows.
1. Turn the key to “OFF” and turn off all electrical
circuits.
CAUTION:

ECB00640
To prevent accidental short-circuiting, turn off
1. Fuse
2. Spare fuse
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