2021 YAMAHA YFZ450R torque

9-27
93. 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. Install the gasket, tailpipe, and retainer and
align the bolt holes.
5. Install the bolts and tighten them to the spec- ified torque.
6. Install the tailpipe cover and align the bolt holes.
7. Install the bolts and tighten them to the spec- ified torque.
1. Bolt
2. Retainer
3. Tailpipe
4. Gasket1
2
3
4
1
1. Tailpipe
2. Spark arresterTightening torque:Retainer bolt:10 N·m (1.0 kgf·m, 7.4 lb·ft)
1
2
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EBU29705Adjusting the throttle lever free playPeriodically check the throttle lever free play and
adjust if necessary.1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle lever free play, turn
the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24062Valve clearanceThe valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance chart.EBU29602BrakesReplacement of brake components requires pro-
fessional knowledge. Brake service should be
performed by a Yamaha dealer.
Tightening torque:
Tailpipe cover bolt:8 N·m (0.8 kgf·m, 5.9 lb·ft)
1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free playThrottle lever free play: 2.0–4.0 mm (0.08–0.16 in)
32
4
(a)(b)
1
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9
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.
[ECB00522]
WARNING
EWB02091Operating 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.
EBU24744Brake light switchesThe brake light, which is activated by the brake
pedal and brake lever, should come on just before
braking takes effect.
The brake light switch for the brake pedal can be
adjusted as follows, but the front brake light
switch should be adjusted by a Yamaha dealer.
Turn the rear brake light switch adjusting nut while
holding the brake light switch in place. To make
the brake light come on earlier, turn the adjusting
nut in direction (a). To make the brake light come
on later, turn the adjusting nut in direction (b).
Tightening torque:
Locknut (rear brake caliper):16 N·m (1.6 kgf·m, 12 lb·ft)1. Rear brake light switch
2. Rear brake light switch adjusting nut
1
2(a) (b)
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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 ATVbackward. 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 prevent this from occurring, keep the drive
chain slack within the specified limits.
[ECB00543]
6. Pull the rod out, and then tighten the rear axle
pinch bolts to the specified torque in the or-
der 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 N·m (2.1 kgf·m, 15 lb·ft)
3 1 2
4
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EBU27484Installing a wheel1. Install the wheel with the arrow mark pointingin the forward rotating direction of the wheel,
and then install the wheel nuts.
2. Lower the ATV to the ground.
3. Tighten the wheel nuts to the specified torques.
EBU25741TroubleshootingAlthough Yamaha ATVs receive a thorough in-
spection before shipment from the factory, trouble
may occur during operation. Any problem in the
fuel, compression, or ignition systems, for exam-
ple, can cause poor starting and loss of power.
The following troubleshooting charts represent
quick and easy procedures for checking these vi-
tal systems yourself. However, should your ATV
require any repair, take it to a Yamaha dealer,
whose skilled technicians have the necessary
tools, experience, and know-how to service the
ATV properly.
Use only genuine Yamaha replacement parts. Im-
itation parts may look like Yamaha parts, but they
are often inferior, have a shorter service life and
can lead to expensive repair bills.
1. Arrow mark
2. Forward rotating direction
3. Wheel nut
2
3
3
Tightening torques: Front wheel nut:45 N·m (4.5 kgf·m, 33 lb·ft)
Rear wheel nut: 45 N·m (4.5 kgf·m, 33 lb·ft)
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