2016 YAMAHA WR 450F checking oil

ELECTRIC STARTER
6-38
EAS2GC1263CHECKING THE STARTER MOTOR
1. Check:•CommutatorDirt  Clean with 600 grit sandpaper.
2. Measure: • Commutator diameter “a”Out of specification  Replace the starter
motor.
3. Measure: • Mica undercut “a”Out of specification  Scrape the mica to
the proper measurement with a hacksaw
blade that has been grounded to fit the com-
mutator.
TIP
The mica of the commutator must be undercut
to ensure proper operation of the commutator.
4. Measure: • Armature assembly resistances (commuta-
tor and insulation)
Out of specification  Replace the starter
motor.
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a. Measure the armature assembly resistanc-
es with the pocket tester.
b. If any resistance is out of specification, re- place the starter motor.
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5. Measure:• Brush length “a”Out of specification  Replace the brush
set.
6. Measure: • Brush spring force
Out of specification  Replace the brush
set.
Limit
16.6 mm (0.65 in)
Mica undercut (depth) 1.50 mm (0.06 in)
Pocket tester90890-03112
Analog pocket tester YU-03112-C
Armature coil Commutator resistance “1” 0.0117–0.0143 
Insulation resistance “2” Above 1 M 
Limit 3.50 mm (0.14 in)
Brush spring force 3.92–5.88 N (400–600 gf, 14.11–
21.17 oz)

CLUTCH
6-46
EAS2GC1276CHECKING THE PRIMARY DRIVEN GEAR
1. Check:• Primary driven gearDamage/wear  Replace the primary drive
and primary driven gears as a set.
Excessive noise during operation  Re-
place the primary drive and primary driven
gears as a set.
EAS2GC1277INSTALLING THE OIL SEAL
1. Install: • Oil seal “1”
• Washer “2”
• Circlip “3”
TIP
• Apply the lithium-soap-based grease on the
oil seal lip.
• Install the oil seal in parallel with its manufac-
ture's marks or numbers facing inward.
EAS2GC1278INSTALLING THE RIGHT CRANKCASE
COVER
1. Install: • Dowel pin “1”
• O-rings “2”
• Collar “3”
• Gasket “4”
TIP
Apply the lithium-soap-based grease on the O-
ring.
2. Install:
• Right crankcase cover “1” • Right crankcase cover bolt “2”
TIP
• Apply the engine oil on the impeller shaft end.
• When installing the crankcase cover onto the
crankcase, make sure that the impeller shaft
end “3” aligns with the balancer end slot “4”.
• Tighten the right crankcase cover bolts in
stages and in a crisscross pattern.
EAS2GC1279INSTALLING THE CLUTCH
1. Install:
• Push lever shaft “1”
TIP
• Apply the lithium-soap-based grease on the oil seal lip.
• Before installation, apply the engine oil to the
push lever shaft sliding surface.
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Right crankcase cover bolt10 Nm (1.0 m·kgf, 7.2 ft·lbf)
T R..
1 2
1

KICKSTATER
6-51
EAS2GC1282REMOVING THE KICK SHAFT ASSEMBLY
1. Remove:• Kick shaft assembly “1”
TIP
Unhook the torsion spring “2” from the hole “a”
in the crankcase.
EAS2GC1283CHECKING THE KICK SHAFT AND RATCH-
ET WHEEL
1. Check:• Ratchet wheel “1” smooth movementUnsmooth movement  Replace.
• Kick shaft “2” Wear/damage  Replace the kick shaft as-
sembly.
• Spring “3” Broken  Replace.
EAS2GC1284CHECKING THE KICK GEAR, KICK IDLE
GEAR AND RATCHET WHEEL
1. Check:
• Kick gear “1”
Wear/damage  Replace the kick shaft as-
sembly.
• Kick idle gear “2”
• Ratchet wheel “3”
• Gear teeth “a”
• Ratchet teeth “b”
Wear/damage  Replace.
EAS2GC1285INSTALLING THE KICK SHAFT ASSEMBLY
1. Install:
• Kick gear “1”
• Washer “2”
• Circlip “3”
• Ratchet wheel “4”
• Spring “5”
• Washer “6”
• Circlip “7”
(to the kick shaft “8”)
TIP
• Apply molybdenum disulfide oil to the inner circumferences of the kick gear and ratchet
wheel.
• Align the punch mark “a” on the ratchet wheel
with the punch mark “b” on the kick shaft.
2. Install: • Torsion spring “1”
(to the kick shaft “2”)
TIP
Make sure the stopper “a” of the torsion spring
fits into the hole “b” on the kick shaft.
3 1
2
a
b 3
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OIL PUMP AND BALANCER GEAR
6-59
EAS2GC1299REMOVING THE BALANCER
1. Loosen:• Balancer nut “1”
• Primary drive gear nut “2”
• Balancer weight gear nut “3”
TIP
Place an aluminum plate “a” between the teeth
of the balancer drive gear “4” and balancer
weight gear “5”.
EAS2GC1300CHECKING THE PRIMARY DRIVE GEAR,
BALANCER SHAFT DRIVE GEAR, AND
BALANCER WEIGHT GEAR
1. Check: • Primary drive gear “1”
• Balancer shaft drive gear “2”
• Balancer weight gear “3”Wear/damage  Replace.
EAS2GC1301CHECKING THE BALANCER
1. Check:
•Balancer
Crack/damage  Replace.
EAS2GC1302CHECKING THE OIL PUMP
1. Check:
• Oil pump drive gear
• Oil pump driven gear
• Oil pump housing
• Oil pump housing coverCracks/damage/wear  Replace the defec-
tive part(s).
2. Measure: • Inner-rotor-to-outer-rotor-tip clearance “a”
• Outer-rotor-to-oil-pump-housing clearance
“b”
• Oil-pump-housing-to-inner-rotor-and-outer-
rotor clearance “c”
Out of specification  Replace the oil pump.
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a
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a
5

CRANKCASE
6-72
EAS2GC1311DISASSEMBLING THE CRANKCASE
1. Separate:• Right crankcase
• Left crankcase
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a. Remove the crankcase bolts.
TIP
Loosen each bolt 1/4 of a turn at a time and af-
ter all the bolts are loosened, remove them.
b. Remove the right crankcase “1”.
TIP
• Place the crankcase with its left side down-ward and split it by inserting a screwdriver tip
into the splitting slit “a” in the crankcase.
• Lift the right crankcase horizontally while light-
ly patting the crankcase splitting slit and the
engine mounting boss using a soft hammer,
and leave the crankshaft and the transmission
with the left crankcase.
ECA33DD041
NOTICE
Use soft hammer to tap on the case half.
Tap only on reinforced portions of case. Do
not tap on gasket mating surface. Work
slowly and carefully. Make sure the case
halves separate evenly. If the cases do not
separate, check for a remaining case bolt or
fitting. Do not force. c. Remove the dowel pins and O-ring.
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EAS2GC1312REMOVING THE CRANKCASE BEARING
1. Remove:
• Bearing “1”
TIP
• Remove the bearing from the crankcase by pressing its inner race.
• Do not use the removed bearing.
EAS2GC1313CHECKING THE TIMING CHAIN, TIMING
CHAIN GUIDE, OIL STRAINER
1. Check:• Timing chainStiffness  Replace the camshaft sprocket,
timing chain and crankshaft sprocket as a
set.
2. Check: • Timing chain guide
Damage/wear  Replace
EAS2GC1314CHECKING THE CRANKCASE
1. Wash:
• Crankcase
TIP
• Wash the crankcase in a mild solvent.
• Remove any remaining gasket from the
crankcase mating surface.
2. Check: • CrankcaseCrack/damage  Replace.
1
a

TRANSMISSION
6-79
EAS2GC1325CHECKING THE SHIFT DRUM ASSEMBLY
1. Check:• Shift drum grooveDamage/scratches/wear  Replace the
shift drum assembly.
• Shift drum segment “1” Damage/wear  Replace the shift drum as-
sembly.
EAS2GC1326CHECKING THE TRANSMISSION
1. Measure: • Main axle runout(with a centering device and dial gauge “1”)
Out of specification  Replace the main ax-
le.
2. Measure: • Drive axle runout(with a centering device and dial gauge “1”)
Out of specification  Replace the drive ax-
le. 3. Check:
• Transmission gears
Blue discoloration/pitting/wear  Replace
the defective gear (s).
• Transmission gear dogs
Cracks/damage/rounded edges  Replace
the defective gear (s).
4. Check:
• Transmission gear movementRough movement  Replace the defective
gear (s).
EAS2GC1327INSTALLING THE TRANSMISSION
1. Install:
• 5th pinion gear (25T) “1”
• 3rd pinion gear (16T) “2”
• Collar “3”
• 4th pinion gear (20T) “4”
• 2nd pinion gear (15T) “5”(to the main axle “6”)
TIP
Before installation, apply molybdenum disulfide
oil to the inner and end surface of the idler gear
and to the inner surface of the sliding gear, then
install.
Main axle runout limit
0.08 mm (0.0032 in)
Drive axle runout limit 0.08 mm (0.0032 in)
3 4
2
1
6
5
M

7
COOLING SYSTEM
RADIATOR....................................................................................................... 7-1
HANDLING NOTE ...................................................................................... 7-3
CHECKING THE RADIATOR ..................................................................... 7-3
WATER PUMP .................................................................................................. 7-4
REMOVING THE OIL SEAL ....................................................................... 7-5
CHECKING THE WATER PUMP ............................................................... 7-5
CHECKING THE BEARING ....................................................................... 7-5
INSTALLING THE OIL SEAL ..................................................................... 7-5
ASSEMBLING THE WATER PUMP........................................................... 7-5

WATER PUMP
7-5
EAS2GC1333REMOVING THE OIL SEAL
TIP
• Remove the oil seal when the coolant level changes frequently more than usual, coolant
has discolored, or engine oil has become
milky.
• Do not use the removed oil seal.
1. Remove:• Oil seals “1”
EAS2GC1334CHECKING THE WATER PUMP
1. Check:
• Water pump housing cover
• Impeller shaftCracks/damage/wear  Replace.
EAS2GC1335CHECKING THE BEARING
1. Check:
• BearingRotate the inner race with your finger.
Rough spot/seizure  Replace.
EAS2GC1336INSTALLING THE OIL SEAL
1. Install:
• Oil seals “1”
TIP
• Apply the lithium-soap-based grease on the oil seal lip.
• Install the oil seal with its manufacture’s marks or numbers facing the right crankcase
cover “2”. 2. Install:
• Bearing “1”
TIP
Install the bearing by pressing its outer race
parallel.
EAS2GC1337ASSEMBLING THE WATER PUMP
1. Install:
• Impeller shaft assembly “1”
•Pin “2”
• Collar “3”
• Circlip “4”
TIP
• Take care so that the oil seal lip is not dam-aged or the spring does not slip off its posi-
tion.
• When installing the impeller shaft, apply the engine oil to the oil seal lip, the bearing, and
the impeller shaft.
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