2018 YAMAHA YFZ450R torque

4-13
4
3. Tighten the locknut to the specified torque. NOTICE: Always tighten the locknut
against the adjusting nut, and then tighten
it to the specified torque.
[ECB00082]
Rebound damping force
Turn the rebound damping force adjusting screw
in direction (a) to increase the rebound damping
force and thereby harden the damping, and in di-
rection (b) to decrease the rebound damping force
and thereby soften the damping.
Spring preload setting:
Minimum (soft):Distance A = 302.5 mm (11.91 in)
Standard: Distance A = 293.0 mm (11.54 in)
Maximum (hard): Distance A = 282.5 mm (11.12 in)
1. Distance A
1
Tightening torque: Locknut:50 N·m (5.0 kgf·m, 37 lb·ft)1. Rebound damping force adjusting screw
(a)
(b)
1
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4-20
410. Tighten the locknut to the specified torque. NOTICE: Always tighten the locknut
against the adjusting nut, and then tighten
it to the specified torque.
[ECB00082]
11. Connect the air intake duct to the throttle body, and then tighten the clamp screw at the
throttle body side. NOTICE: Make sure that
the air intake duct is properly connected to
the throttle body, and that the clamp
screw is tightened securely.
[ECB00962]
12. Connect the coupler.
13. Connect the air filter case to the air intake duct, place the air filter case in the original po-
sition, and then tighten the clamp screw at
the air filter case side. NOTICE: Make sure
that the air intake duct is properly con-
nected to the air filter case, and that the
clamp screw is tightened securely.
[ECB00972]
14. Install the air filter case bolts, and then tighten them to the specified torque.
Spring preload setting:
Minimum (soft):Distance A = 286.5 mm (11.28 in)
Standard: Distance A = 278.0 mm (10.94 in)
Maximum (hard): Distance A = 266.5 mm (10.49 in)
1. Distance A
1
Tightening torque:Locknut:30 N·m (3.0 kgf·m, 22 lb·ft)
Tightening torque: Air filter case bolt:7 N·m (0.7 kgf·m, 5.2 lb·ft)
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4-21
4
15. Install the air filter case holding plate by in-
stalling the bolts and collars, and then tighten
the bolts to the specified torque.
16. Install the blow-by gas chamber by installing the bolt, tighten the bolt to the specified
torque, and then install the clip to the hose
holder.
17. Install the cowling.
Rebound damping force
Turn the rebound damping force adjusting screw
in direction (a) to increase the rebound damping
force and thereby harden the damping, and in di-
rection (b) to decrease the rebound damping force
and thereby soften the damping. Tightening torque:
Air filter case holding plate bolt:7 N·m (0.7 kgf·m, 5.2 lb·ft)
Tightening torque: Blow-by gas chamber bolt:7 N·m (0.7 kgf·m, 5.2 lb·ft)
1. Rebound damping force adjusting screwRebound damping setting: Minimum (soft):30 click(s) in direction (b)*
Standard: 15 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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8-2
8
EBU29572Owner’s manual and tool kitBe sure to always keep the owner’s manual, the
owner’s tool kit and the low-pressure tire gauge
with the vehicle. Make sure to protect the owner’s
manual by putting it in the plastic bag, then by
placing the bag in the document pouch.
The service information included in this manual
and the tools provided in the owner’s tool kit are
intended to assist you in the performance of pre-
ventive maintenance and minor repairs. However,additional tools such as a torque wrench may be
necessary to perform certain maintenance work
correctly.
TIPIf you do not have the tools or experience required
for a particular job, have a Yamaha dealer perform
it for you.
1. Owner’s manual
2. Low-pressure tire gauge
3. Owner’s tool kit
1
2
3
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8-14
8Before installing the spark plug, the spark plug
gap should be measured with a wire thickness
gauge and, 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.
TIPIf a torque wrench is not available when installing
the 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 speci-
fied torque as soon as possible. EBU2949BEngine oil and oil filter elementThe 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 60
°C (140 °F), let it continue to idle for ten sec-
onds or more, and then turn the engine off.
Specified spark plug:
NGK/CR8E
1. Spark plug gapSpark plug gap:0.7–0.8 mm (0.028–0.031 in)
Tightening torque:Spark plug:13 N·m (1.3 kgf·m, 9.6 lb·ft)
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8-18
88. Remove the oil filter element and the O-rings.
9. Install a new oil filter element and new O-
rings.
TIPMake sure that the O-rings are properly seated. 10. 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-ringTightening torque:Oil filter element cover bolt:10 N·m (1.0 kgf·m, 7.4 lb·ft)
1
2
2
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8-19
8
11. Install the crankcase engine oil drain bolt, the
engine oil tank drain bolt and their new gas-
ket, and then tighten the bolts to their speci-
fied torques.
12. Refill with the specified amount of the recom- mended engine oil through the engine oil tank
filler hole.
TIPBe sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down.
NOTICEECB00301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. 13. Check the engine oil tank filler cap O-ring for
damage, and replace it if necessary.
14. Install and tighten the engine oil tank filler cap.
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 level and correct it if necessary.
17. Install the engine guard by installing the bolts, and then tighten them to the specified torque.
NOTICE: Be sure to apply LOCTITE
® to the
engine guard bolts before installing them.
[ECB00372]
Tightening torques: Crankcase engine oil drain bolt:20 N·m (2.0 kgf·m, 15 lb·ft)
Engine oil tank drain bolt: 20 N·m (2.0 kgf·m, 15 lb·ft)
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)
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8-20
8
EBU29861CoolantThe coolant level should be checked before each
ride. In addition, the coolant must be changed at
the intervals specified in the periodic maintenance
and lubrication chart. Have a Yamaha dealer
change the coolant. WARNING! Never attempt
to remove the radiator cap when the engine is
hot.
[EWB02671]
EBU27945
To check the coolant level 1. Place the ATV on a level surface.TIPThe 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.
TIPThe coolant should be between the minimum and
maximum level marks. 3. If the coolant is at or below the minimum levelmark, remove the coolant reservoir cap, add
coolant or distilled water to the maximum lev-
el mark, and then install the reservoir cap.
NOTICE: If coolant is not available, use
distilled water or soft tap water instead.
Do not use hard water or salt water since
they are harmful to the engine. If water has
Tightening torque:
Engine guard bolt:7 N·m (0.7 kgf·m, 5.2 lb·ft)1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
1
2
3
UBW261E0.book Page 20 Friday, May 26, 2017 9:38 AM