2012 YAMAHA YFZ450 torque

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8
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 and the gasket. 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. Check the gasket for damage, and replace it if necessary.
10. Install the gasket and the purging bolt, and then tighten the bolt to the specified torque.
1. Tailpipe
2. Spark arresterTightening torque:Tailpipe bolt:10 Nm (1.0 m ·kgf, 7.2 ft· lbf)
1
2
1. Purging bolt
2. Gasket
1
2
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WARNING
EWB02380Never 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.EBU23940Adjusting 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 aYamaha 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-
tenance.
NOTICEECB00480The carburetor has been set and extensively
tested at the Yamaha factory. Changing these
settings without sufficient technical knowl-
edge may result in poor performance of or
damage to the engine.EBU24030Checking the engine idling speed A special tester is needed to check the engine
idling speed on this model.
Therefore, take the ATV to a Yamaha dealer to
have the engine idling speed checked and adjust-
ed.
Tightening torque:
Purging bolt:27 Nm (2.7 m ·kgf, 20 ft· lbf)Engine idling speed:
1750 –1850 r/min
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8
TIPIf the cable length cannot be adjusted to specifica-
tion, consult a Yamaha dealer.6. Tighten the locknut on the brake cable.
7. Slide the rubber cover to its original position.
8. Turn in the adjusting bolt at the rear brake cal-iper until it feels tight, then turn it out 1/8 turn
and tighten its locknut to the specified torque.
NOTICE: When tightening the locknut, hold the adjusting bolt with a wrench so
that it does not turn together with the lock-
nut.
[ECB00521]
WARNING
EWB02090Operating with improperly serviced or adjust-
ed brakes could cause the brakes to malfunc-
tion, resulting in reduced braking
performance. This could increase the chance
of a collision or accident. After adjusting the
parking brake free play, block the rear of the
ATV off the ground and spin the rear wheels.
Check to make sure there is no brake drag. If
brake drag is noticed, perform the adjustment
again.EBU24743Brake light switches The brake light, which is activated by the brake
pedal and brake lever, should come on just before
braking takes effect.
1. Locknut
2. Parking brake free play adjusting nut
3. Rubber cover
(a)
(b)
1
2
3
Tightening torque: Locknut (rear brake caliper):16 Nm (1.6 m ·kgf, 12 ft· lbf)
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8
TIPA rod can be obtained at a Yamaha dealer to make
this adjustment.4. Shift the transmission into neutral.
5. To tighten the drive chain, push the ATV back-ward. To loosen the drive chain, push the ATV
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 pre- vent this from occurring, keep the drive
chain slack within the specified limits.
[ECB00542]
6. Pull the rod out, and then tighten the rear axle
pinch bolts to the specified torque in the order
shown.
1. Rear wheel axle pinch bolt
2. Rod
3. Drive chain tensioner
4. Hole
3
4
2 11
Tightening torque:
Rear axle pinch bolt:21 Nm (2.1 m ·kgf, 15 ft· lbf)
31 2
4
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8
Front
Rear
3. Elevate the ATV and place a suitable stand
under the frame.
4. Remove the nuts from the wheel.
5. Remove the wheel.
EBU25661Installing a wheel 1. Place the ATV on a level surface.
2. Install the wheel and the nuts.
3. Lower the ATV to the ground.
4. Tighten the wheel nuts to the specified torques.EBU25740Troubleshooting Although Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the fu-
el, compression, or ignition systems, for example,
can cause poor starting and loss of power.
1. Nut
1. Nut
Tightening torques:Front wheel nut:45 Nm (4.5 m ·kgf, 33 ft ·lbf)
Rear wheel nut: 45 Nm (4.5 m ·kgf, 33 ft ·lbf)
U1PD60E0.book Page 55 Monday, June 13, 2011 2:57 PM