Page 115 of 154
8-26
8
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. 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, 7.2 lb·ft)
1
2
UBW260E0.book Page 26 Thursday, May 12, 2016 2:28 PM
Page 116 of 154

8-27
8
WARNING
EWB02341Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
touching exhaust components. EBU29703Adjusting the throttle lever free playThe throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The throttle lever free play should measure 2.0–4.0
mm (0.08–0.16 in) as shown. Periodically check
the throttle lever free play and, if necessary, adjust
it as follows.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.
EBU24061Valve clearanceThe valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
Tightening torque:
Tailpipe cover bolt:8 N·m (0.8 kgf·m, 5.8 lb·ft)1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
32
4
(a)(b)
1
UBW260E0.book Page 27 Thursday, May 12, 2016 2:28 PM
Page 121 of 154

8-32
8
Cable length “A” should measure 47–51 mm
(1.85–2.01 in). Adjust the parking brake free play
as follows.
1. Release the parking brake by moving the parking brake lever to the right.
2. Fully loosen the locknut and the adjusting bolt at the rear brake caliper.
3. Slide the rubber cover back at the brake ca- ble.
4. Loosen the locknut. 5. Turn the parking brake free play adjusting nut
in direction (a) to increase the cable length,
and in direction (b) to decrease it.
TIPIf the cable length cannot be adjusted to specifi-
cation, 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.
1. Adjusting bolt
2. Cable length “A”
3. Locknut
1
2
3
1. Locknut
2. Parking brake free play adjusting nut
3. Rubber cover
1
2
3
(b)
(a)
UBW260E0.book Page 32 Thursday, May 12, 2016 2:28 PM
Page 122 of 154
![YAMAHA YFZ450R 2017 Owners Manual 8-33
8NOTICE:
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 o YAMAHA YFZ450R 2017 Owners Manual 8-33
8NOTICE:
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 o](/manual-img/51/53837/w960_53837-121.png)
8-33
8NOTICE:
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).
EBU30153Adjusting the clutch lever free playThe clutch lever free play must be checked and, if
necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
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)
UBW260E0.book Page 33 Thursday, May 12, 2016 2:28 PM
Page 125 of 154
8-36
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 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
UBW260E0.book Page 36 Thursday, May 12, 2016 2:28 PM
Page 137 of 154
8-48
8
EBU26921Tail/brake lightThis model is equipped with an LED type of
tail/brake light.
If the tail/brake light does not come on, have a
Yamaha dealer check it.EBU25652Removing a wheel1. Place the ATV on a level surface.
2. Loosen the wheel nuts.
3. Elevate the ATV and place a suitable stand under the frame.
4. Remove the nuts from the wheel.
5. Remove the wheel.
EBU27483Installing a wheel1. Install the wheel and the nuts.TIPWhen installing the wheel, make sure its arrow
mark points toward the rotating direction of
the wheel. 2. Lower the ATV to the ground.
3. Tighten the wheel nuts to the specified torques.
1. Wheel nut
1. Arrow mark
UBW260E0.book Page 48 Thursday, May 12, 2016 2:28 PM
Page 138 of 154

8-49
8
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.
WARNING
EWB02281Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe inju-
ry or property damage. Make sure there are no
open flames or sparks in the area, including pi-
lot lights from water heaters or furnaces.
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)
UBW260E0.book Page 49 Thursday, May 12, 2016 2:28 PM