2009 YAMAHA YFZ450R torque

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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:
50 Nm (5.0 m·kgf, 36 ft·lbf)
1. Rebound damping force adjusting screw
Rebound damping setting:
Minimum (soft):
20 click(s) in direction (b)*
Standard:
12 click(s) in direction (b)*
Maximum (hard):
1 click(s) in direction (b)*
* With the adjusting screw fully turned in di-
rection (a)
1
(a)
(b)

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(0.06 in). 10. 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.
11. Place the air filter case in the original position,
install the bolts, and then tighten them to the
specified torque.
12. Connect the air intake duct to the air filter
case, and then tighten the clamp screw at the
air filter case side.
NOTICE
ECB00970
Make sure that the air intake duct is properly
connected to the air filter case, and that the
Spring preload setting:
Minimum (soft):
Distance A = 273.5 mm (10.77 in)
Standard:
Distance A = 265.0 mm (10.43 in)
Maximum (hard):
Distance A = 253.5 mm (9.98 in)
1. Distance A
1

Tightening torque:
Locknut:
30 Nm (3.0 m·kgf, 22 ft·lbf)
Tightening torque:
Bolt:
6.5 Nm (0.7 m·kgf, 4.7 ft·lbf)

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clamp screw is tightened securely.
13. Install the blow-by gas chamber by installing
the bolt, and then tighten it to the specified
torque.
14. Install the air filter case holding plate by install-
ing the bolts and collars.
15. Connect the coupler.
16. Connect the air intake duct to the throttle
body, and then tighten the clamp screw at the
throttle body side.
NOTICE

ECB00960
Make sure that the air intake duct is properly
connected to the throttle body, and that the
clamp screw is tightened securely.
17. Install the panel.
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 therebound damping force and thereby soften the
damping.
Tightening torque:
Bolt:
6.5 Nm (0.7 m·kgf, 4.7 ft·lbf)

1. Position indicator marks
2. Rebound damping force adjusting screw
Rebound damping setting:
Minimum (soft):
20 turn(s) out from the fully turned in posi-
tion
Standard:
11 turn(s) out from the fully turned in posi-
tion
Maximum (hard):
1 turn(s) out from the fully turned in position
12
(a) (b)

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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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EBU29440
Checking the spark plug
The spark plug is an important engine component,
which should be checked periodically, preferably
by a Yamaha dealer. Since heat and deposits will
cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
The porcelain insulator around the center elec-
trode of the spark plug should be a medium-to-light
tan (the ideal color when the vehicle is ridden nor-
mally). If the spark plug shows a distinctly different
color, the engine could be operating improperly.
Do not attempt to diagnose such problems your-
self. Instead, have a Yamaha dealer check the ve-
hicle.
If a spark plug shows signs of electrode erosion
and excessive carbon or other deposits, it should
be replaced.
Before installing a spark plug, the spark plug gap
should be measured with a wire thickness gaugeand, if necessary, adjusted to specification.
Clean the surface of the spark plug gasket and its
mating surface, and then wipe off any grime from
the spark plug threads.
Specified spark plug:
NGK/CR8E
1. Spark plug gap
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Tightening torque:
Spark plug:
12.5 Nm (1.3 m·kgf, 9.4 ft·lbf)

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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.
EBU29492
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.
To check the engine oil level
1. Place the ATV on a level surface.
2. Start the engine, warm it up until the engine oil
has reached a normal temperature of 40 °C
(104 °F), let it continue to idle for ten seconds
or more, and then turn the engine off.
TIP

To achieve the proper engine oil temperature for
an accurate oil level reading, the engine must have
first completely cooled down, and then warmed up
again for several minutes to normal operating tem-
perature.
3. Remove the engine oil tank filler cap, and
wipe the dipstick off with a clean rag.
4. Insert the dipstick into the filler hole (without
screwing it in), and then remove it again to
check the oil level.TIP

The engine oil should be between the minimum
1. Engine oil tank filler cap
2. Dipstick
3. Maximum level mark
4. Minimum level mark
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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
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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)
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12. Install the crankcase engine oil drain bolt and
the engine oil tank drain bolt, and then tighten
them to their 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.
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,
do not use oils labeled “ENERGY CONSERV-
ING II” or higher.

Make sure that no foreign material enters the
crankcase.
14. Start the engine, and then let it idle for several Tightening torques:
Crankcase engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Engine oil tank drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter element replacement:
1.40 L (1.48 US qt, 1.23 Imp.qt)
With oil filter element replacement:
1.45 L (1.53 US qt, 1.28 Imp.qt)
1. “CD” specification
2. “ENERGY CONSERVING II”
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