2016 YAMAHA WR 450F check engine

ENGINE
3-21
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5. Adjust:• Valve clearance
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a. Remove the camshaft (intake and exhaust). Refer to “CAMSHAFT” on page 6-11.
b. Remove the valve lifter “2” and the adjusting
pad “3” with a valve lapper “1”.
TIP
• Place a cloth in the timing chain space to pre-vent adjusting pads from falling into the crank-
case.
• Identity each valve lifter and adjusting pad po-
sition very carefully so that they can be rein-
stalled in their original place. c. Check the number on the originally installed
adjusting pad.
TIP
• The adjusting pad number “a” is indicated on the top of the adjusting pad.
• For the number on the originally installed ad- justing pad, convert the last digit of adjusting
pad number as per the below table.
d. Select an adjusting pad with a proper valve clearance from the adjusting pad selection
table.
TIP
• There are 25 types of adjusting pads, ranging from 1.20 mm (0.0472 in) to 2.40 mm (0.0945
in), in increments of 0.05 mm (0.0020 in).
• The field where the number on the originally installed adjusting pad and the measured
valve clearance intersect shows the adjusting
pad number to replace.
Example:
Pad number = 148
Rounded value = 150
Valve lapper
90890-04101
Valve lapping tool YM-A8998
e e
1
1
3 2Last digit of pad
number Rounded valve
0, 1 or 2 0
4, 5 or 6 5 8 or 9 10

ENGINE
3-22
e. Install the new adjusting pads “4” and the valve lifters “5”.
ECA
NOTICE
Do not twist adjusting pads and valve lifters
forcibly during installation.
TIP
• Apply the engine oil on the valve lifters.
• Apply molybdenum disulfide oil to the valve stem ends.
• Check that the valve lifters turn smoothly when rotated with your finger.
• Make sure that valve lifters and adjusting pads are installed in place.
• Make sure that adjusting pads are installed
with their numbers facing upward.
f. Install the camshafts (exhaust and intake). Refer to “CAMSHAFT” on page 6-11.
g. Measure the valve clearance again.
h. If the valve clearance is out of specification, repeat adjusting the valve clearance until it
is within specification.
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4
5

CHASSIS
3-31
• When refilling, be careful that water does not enter the brake fluid reservoir. Water
will significantly lower the boiling point of
the brake fluid and could cause vapor
lock.
ECA
NOTICE
Brake fluid may damage painted surfaces
and plastic parts. Therefore, always clean
up any spilt brake fluid immediately.
EAS2GC1110ADJUSTING THE DRIVE CHAIN SLACKECA
NOTICE
A drive chain that is too tight will overload
the engine and other vital parts, and one
that is too loose can skip and damage the
swingarm or cause an accident. Therefore,
keep the drive chain slack within the speci-
fied limits.
1. Use a suitable stand to raise the rear wheel off the ground.
EWA
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Shift the transmission into the neutral posi-
tion.
3. Pull the drive chain up above the drive chain guide installation bolt with a force of about
50 N (5.0 kgf, 36 lbf).
4. Check: • Drive chain slack “a”
Out of specification  Regulate.
TIP
Measure drive chain slack between the drive
chain guide and the bottom of the chain as
shown. 5. Adjust:
• Drive chain slack
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a. Loosen the wheel axle nut “1”.
b. Loosen both locknuts “2”.
c. Turn the adjusting bolt “3” in direction “a” or “b” until the specified drive chain slack is ob-
tained.
TIP
• To maintain the proper wheel alignment, ad-just both sides evenly.
• Push the rear wheel forward to make sure that
there is no clearance between the swingarm
end plates and the ends of the swingarm.
d. Tighten the locknut.
e. Tighten the wheel axle nut.
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EAS2GC1111CHECKING THE FRONT FORK LEGS
1. Stand the vehicle upright on a level surface.
EWA
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Check: • Inner tubeDamage/scratches  Replace.
• Front fork leg (s) Oil leaks between inner tube and outer tube
 Replace the oil seal.
Drive chain slack (on a suitable
stand)
50.0–60.0 mm (1.97–2.36 in)
a
Direction “a”The drive chain slack decreases.
Direction “b” The drive chain slack increases.
Locknut21 Nm (2.1 m·kgf, 15 ft·lbf)
Wheel axle nut 125 Nm (12.5 m·kgf, 90 ft·lbf)
1
32
a
b
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CHASSIS
3-38
c. Turn the front fork to the right and left a few times, and make sure that the steering ro-
tates smoothly. If it does not turn smoothly,
remove the lower bracket and check the up-
per and lower bearings.
Refer to “STEERING HEAD” on page 5-53.
d. Loosen the ring nut fully turn and then tight- en it to specification with a steering nut
wrench.
EWA
WARNING
Do not overtighten the lower ring nut.
e. Check the steering head for looseness or binding by turning the front fork all the way in
both directions. If any binding is felt, remove
the lower bracket and check the upper and
lower bearings.
Refer to “STEERING HEAD” on page 5-53.
f. Install the washer “1”.
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5. Install: • Upper bracketRefer to “STEERING HEAD” on page 5-53.
• Handlebar
Refer to “HANDLEBAR” on page 5-33.
EAS2GC1124CHECKING AND LUBRICATING THE CA-
BLES
The following procedure applies to all of the in-
ner and outer cables.
EWA
WARNING
Damaged outer cable may cause the cable
to corrode and interfere with its movement.
Replace damaged outer cable and inner ca-
bles as soon as possible.
1. Check:• Outer cableDamage  Replace.
2. Check: • Cable operationRough movement  Lubricate.
TIP
Hold the cable end upright and pour a few
drops of lubricant into the cable sheath or use
a suitable lubricating device.
EAS2GC1125LUBRICATING THE LEVERS
1. Lubricate the pivoting points and metal-to-
metal moving parts of the following parts.
•Brake lever
• Clutch lever
EAS2GC1126LUBRICATING THE PEDAL
1. Lubricate the pivoting point and metal-to-
metal moving parts of the pedal.
Steering nut wrench
90890-01403
Exhaust flange nut wrench YU-A9472
Ring nut (initial tightening torque) 38 Nm (3.8 m·kgf, 27 ft·lbf)
Ring nut (final tightening torque) 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
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Recommended lubricantEngine oil or a suitable cable lu-
bricant
Recommended lubricant Silicone grease
Recommended lubricant Lithium-soap-based grease
Recommended lubricant Lithium-soap-based grease

CHASSIS
3-39
EAS2GC1127LUBRICATING THE DRIVE CHAIN
The drive chain consists of many interacting
parts. If the drive chain is not maintained prop-
erly, it will wear out quickly. Therefore, the drive
chain should be serviced, especially when the
vehicle is used in dusty areas.
This vehicle has a drive chain with small rubber
O-rings between each side plate. Steam clean-
ing, high-pressure washing, certain solvents,
and the use of a coarse brush can damage
these O-rings. Therefore, use only kerosene to
clean the drive chain. Wipe the drive chain dry
and thoroughly lubricate it with engine oil or
chain lubricant that is suitable for O-ring chains.
Do not use any other lubricants on the drive
chain since they may contain solvents that
could damage the O-rings.
EAS2GC1128LUBRICATING THE SIDESTAND
Lubricate the pivoting point and metal-to-metal
moving parts of the sidestand.
EAS2GC1129CHECKING THE CHASSIS FASTENERS
Make sure that all nuts, bolts, and screws are
properly tightened.
Refer to “CHASSIS TIGHTENING TORQUES”
on page 2-17.Recommended lubricant
Chain lubricant suitable for O-
ring chains
Recommended lubricant Lithium-soap-based grease

ELECTRICAL SYSTEM
3-41
2. Attach:• Timing light “1”
• Digital tachometer “2”To the high tension code “3”.
3. Adjust: • Engine idling speedRefer to “ADJUSTING THE ENGINE
IDLING SPEED” on page 3-19.
4. Check: • Ignition timingCheck whether the alignment mark “a” on
the left crankcase cover is within the firing
range “b” on the rotor.
Incorrect firing range  Check rotor and
Crankshaft position sensor.
5. Install: • Timing mark accessing screwEAS2GC1133CHECKING AND CHARGING THE BATTERY
Refer to “CHECKING AND CHARGING THE
BATTERY” on page 9-69.
EAS2GC1134REPLACING THE HEADLIGHT BULBEWA
WARNING
Since the headlight bulb gets extremely hot,
keep flammable products and your hands
away from the bulb until it has cooled down.
1. Remove:• Headlight unit bolt “1”
TIP
After you have removed the headlight unit
bolts, lift and remove the headlight unit.
2. Remove:
• Headlight coupler “1”
• Bulb cover “2”
3. Remove: • Headlight bulb “1”
Timing light
90890-03141
Timing light YU-03141
Digital tachometer 90890-06760
Digital tachometer YU-39951-B
Timing mark accessing screw 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
2
1
3
ba
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1
2
1

6
ENGINE
ENGINE REMOVAL......................................................................................... 6-1
REMOVING THE SILENCER ..................................................................... 6-6
REMOVING THE EXHAUST PIPE 2.......................................................... 6-6
REMOVING THE DRIVE SPROCKET ....................................................... 6-6
REMOVING THE ENGINE ......................................................................... 6-7
CLEANING THE SPARK ARRESTER ....................................................... 6-7
CHECKING THE SILENCER AND EXHAUST PIPE.................................. 6-8
INSTALLING THE ENGINE........................................................................ 6-8
INSTALLING THE BRAKE PEDAL ............................................................ 6-9
INSTALLING THE DRIVE SPROCKET...................................................... 6-9
INSTALLING THE EXHAUST PIPE AND MUFFLER................................. 6-9
CAMSHAFT .................................................................................................... 6-11
REMOVING THE CAMSHAFT ................................................................. 6-13
CHECKING THE CAMSHAFT.................................................................. 6-14
CHECKING THE TIMING CHAIN AND CAMSHAFT SPROCKET .......... 6-15
CHECKING THE TIMING CHAIN TENSIONERS .................................... 6-15
CHECKING THE DECOMPRESSION SYSTEM.............. ........................ 6-16
INSTALLING THE CAMSHAFTS ............................................................. 6-16
CYLINDER HEAD ........................................................................................... 6-18
REMOVING THE CYLINDER HEAD........................................................ 6-20
CHECKING THE TIMING CHAIN GUIDE (INTAKE SIDE) ...................... 6-20
CHECKING THE CYLINDER HEAD ........................................................ 6-20
INSTALLING THE CYLINDER HEAD ...................................................... 6-21
VALVES AND VALVE SPRINGS ................................................................... 6-23
REMOVING THE VALVES ....................................................................... 6-24
CHECKING THE VALVES AND VALVE GUIDES ................................... 6-25
CHECKING THE VALVE SEATS ............................................................. 6-26
CHECKING THE VALVE SPRINGS......................................................... 6-28
CHECKING THE VALVE LIFTERS .......................................................... 6-29
INSTALLING THE VALVES ..................................................................... 6-29
CYLINDER AND PISTON ............................................................................... 6-31
REMOVING THE PISTON ....................................................................... 6-32
CHECKING THE CYLINDER AND PISTON ............................................ 6-32
CHECKING THE PISTON RINGS............................................................ 6-33
CHECKING THE PISTON PIN ................................................................. 6-34
INSTALLING THE PISTON AND CYLINDER .......................................... 6-34
ELECTRIC STARTER .................................................................................... 6-36
CHECKING THE STARTER MOTOR ...................................................... 6-38
ASSEMBLING THE STARTER MOTOR .................................................. 6-39

ENGINE REMOVAL
6-8
5. Install:• Spark arrester gasket
• Spark arresterInsert the spark arrester into the muffler and
align the bolt holes.
• Tail pipe gasket
• Spark arrester bolts
6. Install: • Muffler cap
TIP
First tighten the two screws “a” located horizon-
tally apart, and then tighten the others.
EAS2GC1232CHECKING THE SILENCER AND EXHAUST
PIPE
1. Check:•Gasket “1”Damage  Replace.
EAS2GC1233INSTALLING THE ENGINE
1. Install:
• Engine “1”Install the engine from the right side.
• Pivot shaft “2” • Engine mounting bolt (lower side) “3”
• Front engine bracket “4”
• Engine bracket bolt (front side) “5”
• Engine mounting bolt (front side) “6”
• Upper engine bracket “7”
• Engine bracket bolt (upper side) “8”
• Engine mounting bolt (upper side) “9”
TIP
Apply molybdenum disulfide grease to the pivot
shaft.
Spark arrester bolt
9 Nm (0.9 m·kgf, 6.5 ft·lbf)
Muffler cap screw 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
Pivot shaft 85 Nm (8.5 m·kgf, 61 ft·lbf)
New
New
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1
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Engine mounting bolt (lower side)53 Nm (5.3 m·kgf, 38 ft·lbf)
Engine bracket bolt (front side) 34 Nm (3.4 m·kgf, 25 ft·lbf)
Engine mounting bolt (front side) 55 Nm (5.5 m·kgf, 40 ft·lbf)
Engine bracket bolt (upper side) 34 Nm (3.4 m·kgf, 25 ft·lbf)
Engine mounting bolt (upper
side) 45 Nm (4.5 m·kgf, 33 ft·lbf)
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78
9
9
8
7
4
1
2
4 3
5
5
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