torque YAMAHA YFZ450 2009 Owners Manual

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3. Tighten the locknut to the specified torque.
NOTICE

ECB00080
Always tighten the locknut against the adjust-
ing nut, and then tighten it to the specified
torque.
Rebound damping force
Turn the adjusting screw in direction (a) to increase
the rebound damping force and thereby harden
the damping, and in direction (b) to decrease the
rebound damping force and thereby soften the
damping.Tightening torque:
Locknut:
30 Nm (3.0 m·kgf, 22 ft·lbf)
1. Rebound damping force adjusting screw
Rebound damping setting:
Minimum (soft):
20 click(s) in direction (b)*
Standard:
10 click(s) in direction (b)*
Maximum (hard):
1 click(s) in direction (b)*
* With the adjusting screw fully turned in di-
rection (a)
(b)
(a)
1

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(0.06 in). 6. Tighten the locknut to the specified torque.
NOTICE

ECB00080
Always tighten the locknut against the adjust-
ing nut, and then tighten it to the specified
torque.
7. Place the air filter case in the original position,
connect the air intake duct, and then tighten
the clamp screw at the carburetor side.
8. Install the bolts, and then connect the hose.
9. Install the seat.
Rebound damping force
Turn the adjusting screw in direction (a) to increase
the rebound damping force and thereby harden
the damping, and in direction (b) to decrease the
rebound damping force and thereby soften the
damping. Spring preload setting:
Minimum (hard):
Distance A = 250.0 mm (9.84 in)
Standard:
Distance A = 257.0 mm (10.12 in)
Maximum (soft):
Distance A = 265.0 mm (10.43 in)

1. Distance A
1

Tightening torque:
Locknut:
44 Nm (4.4 m·kgf, 33 ft·lbf)

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The service information included in this manual
and the tools provided in the owner’s tool kit are in-
tended to assist you in the performance of preven-
tive maintenance and minor repairs. However,
additional tools such as a torque wrench may be
necessary to perform certain maintenance work
correctly.
TIP

If you do not have the tools or experience required
for a particular job, have a Yamaha dealer perform
it for you.
WARNING

EWB01850
Never modify this ATV through improper in-
stallation or use of accessories, as it may
cause changes in handling, which in some sit-
uations could lead to an accident. All parts and
accessories added to this ATV should be gen-
uine Yamaha or equivalent components de-
signed for use on this ATV and should be
installed and used according to instructions. If
you have questions, consult an authorized
Yamaha ATV dealer.

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2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.
3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque.
TIP

If a torque wrench is not available when installing
a spark plug, a good estimate of the correct torque
is 1/4–1/2 turn past finger tight. However, the spark
plug should be tightened to the specified torque as
soon as possible.
4. Install the spark plug cap.
5. Place the fuel tank in the original position, and
then install the bolt.
6. Remove the fuel tank cap by turning it coun-
terclockwise.
7. Place the panel in the original position.8. Install the fuel tank cap by turning it clockwise.
9. Install the bolts and the quick fastener screws.
10. Install the seat.
EBU23304
Engine oil and oil filter element
The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart. Tightening torque:
Spark plug:
12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
1. Projection
2. Slot
21

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9. Check the O-rings for damage, and replace
them if necessary.10. Install a new oil filter element and the O-rings.
TIP

Make sure that the O-rings are properly seated.
11. Install the oil filter element cover by installing
the bolts, and then tighten them to the speci-
fied torque.
1. Oil filter element cover
2. Bolt
1 2

1. Oil filter element
2. O-ring
Tightening torque:
Oil filter element cover bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1
2 2

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12. Install the crankcase engine oil drain bolt and
the engine oil tank drain bolt, and then tighten
them to the specified torques.
13. Pour the specified amount of the recommend-
ed engine oil through the engine oil tank filler
hole, and then install and tighten the engine oil
tank filler cap.
14. Pour the specified amount of the recommend-
ed engine oil through the crankcase engine oil
filler hole, and then install and tighten thecrankcase engine oil filler cap.
TIP

Be sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down.
NOTICE

ECB00300

In order to prevent clutch slippage (since the
engine oil also lubricates the clutch), do not
mix any chemical additives. Do not use oils
with a diesel specification of “CD” or oils of
a higher quality than specified. In addition,
Tightening torques:
Crankcase engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Engine oil tank drain bolt:
19 Nm (1.9 m·kgf, 14 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter element replacement:
Quantity in oil tank:
1.55 L (1.64 US qt, 1.36 Imp.qt)
Quantity in crankcase:
0.20 L (0.21 US qt, 0.18 Imp.qt)
With oil filter element replacement:
Quantity in oil tank:
1.55 L (1.64 US qt, 1.36 Imp.qt)
Quantity in crankcase:
0.30 L (0.32 US qt, 0.26 Imp.qt)

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do not use oils labeled “ENERGY CONSERV-
ING II” or higher.

Make sure that no foreign material enters the
crankcase.
15. 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.
16. Turn the engine off, and then check the oil lev-
el and correct it if necessary.
17. Install the engine guard by installing the bolts,
and then tighten them to the specified torque.
NOTICE

ECB00370
Be sure to apply LOCTITE® to the engine
guard bolts before installing them.
EBU23470
Coolant
The coolant level should be checked before each
ride. In addition, the coolant must be changed atthe intervals specified in the periodic maintenance
and lubrication chart.
EBU23491
To check the coolant level
1. Place the ATV on a level surface.
TIP

The coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture.
2. Check the coolant level in the coolant reser-
voir.
TIP

The coolant should be between the minimum and
maximum level marks. Tightening torque:
Engine guard bolt:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)

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7. After draining the coolant, thoroughly flush the
cooling system with clean tap water.
8. Install the coolant reservoir by installing the
bolts.
9. Replace the coolant drain bolt washer if it is
damaged, install the coolant drain bolt, and
then tighten it to the specified torque.10. Pour the recommended coolant into the reser-
voir to the maximum level mark, and then in-
stall the reservoir cap.
11. Pour the recommended coolant into the radia-
tor until it is full.NOTICE

ECB00401

If coolant is not available, use distilled water
or soft tap water instead. Do not use hard wa-
ter or salt water since it is harmful to the en-
gine.

If water has been used instead of coolant, re-
place it with coolant as soon as possible,
1. Coolant reservoir cap
2. Coolant reservoir
3. Bolt
Tightening torque:
Coolant drain bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1 3
2

Antifreeze/water mixture ratio:
1:1
Recommended antifreeze:
High-quality ethylene glycol antifreeze con-
taining corrosion inhibitors for aluminum en-
gines
Coolant quantity:
Radiator capacity (including all routes):
1.30 L (1.37 US qt, 1.14 Imp.qt)
Coolant reservoir capacity (up to the maxi-
mum level mark):
0.29 L (0.31 US qt, 0.26 Imp.qt)

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EBU27701
Cleaning the spark arrester
Select a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
1. Remove the bolt.
2. Remove the tailpipe by pulling it out of the
muffler.
3. Tap the tailpipe lightly, and then use a wire
brush to remove any carbon deposits from the
spark arrester portion of the tailpipe and inside
of the tailpipe housing.4. Insert the tailpipe into the muffler and align the
bolt holes.
5. Install the bolt and tighten it to the specified
torque.
6. Remove the purging bolt.
1. Bolt
1

1. Tailpipe
2. Spark arrester
Tightening torque:
Tailpipe bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1
2

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7. Start the engine and rev it up approximately
twenty times while momentarily creating ex-
haust system back pressure by blocking the
end of the muffler with a shop towel.
8. Stop the engine and allow the exhaust pipe to
cool.
9. Install the purging bolt and tighten it to the
specified torque.WARNING
EWB02380
Never run the engine in an enclosed area when
purging the spark arrester, otherwise it could
cause injury to the eyes, burns, carbon monox-
ide poisoning, possibly leading to death, and
start a fire.

Always let the exhaust system cool prior to
touching exhaust components.

Always wear eye protection, and make sure
no one is behind the ATV.

Make sure there are no combustible materi-
als in the area.
EBU23940
Adjusting the carburetor
The carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the peri-
odic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. Therefore,
most carburetor adjustments should be left to a
Yamaha dealer, who has the necessary profes-
sional knowledge and experience. The adjustment
described in the following section, however, may
be performed by the owner as part of routine main-
1. Purging bolt
2. Gasket
Tightening torque:
Purging bolt:
27 Nm (2.7 m·kgf, 20 ft·lbf)
1 2