2016 YAMAHA WR 450F transmission

CRANKSHAFT ASSEMBLY AND BALANCER SHAFT
6-74
EAS2GC1317
CRANKSHAFT ASSEMBLY AND BALANCER SHAFT
Removing the crankshaft assembly and balancer shaft
Order Part name Q’tyRemarks
Crankcase Separate.
Refer to “CRANKCASE” on page 6-69.
Transmission Refer to “TRANSMISSION” on page 6-77.
1 Balancer shaft 1
2 Crankshaft assembly 1
For installation, reverse the removal proce-
dure.
1
2

TRANSMISSION
6-77
EAS2GC1322
TRANSMISSION
Removing the transmission, shift drum assembly, and shift forks
OrderPart name Q’tyRemarks
Engine Refer to “ENGINE REMOVAL” on page 6-1.
Crankcase Separate.
Refer to “CRANKCASE” on page 6-69.
1 Main axle 1
2 Drive axle 1
3 Long shift fork guide bar 1
4 Short shift fork guide bar 1
5Spring 4
6 Shift cam 1
7 Shift fork 3 (R) 1
8 Shift fork 2 (C) 1
9 Shift fork 1 (L) 1
10 Collar 1
For installation, reverse the removal proce-
dure.
2
10
1 5 3
4
5
7
8
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TRANSMISSION
6-78
EAS2GC1323REMOVING THE TRANSMISSION
1. Remove:• Long shift fork guide bar “1”
• Short shift fork guide bar “2”
• Shift cam “3”
• Shift fork 3 “4”
• Shift fork 2 “5”
• Shift fork 1 “6”
• Main axle “7”
• Drive axle “8”
• Collar “9”
TIP
• Remove assembly with the collar “9” installed to the crankcase.
• Make a note of the position of each part. Pay particular attention to the location and direc-
tion of shift forks.
• Remove the main axle and the drive axle all together by tapping the drive axle lightly with
a soft hammer.
EAS2GC1324CHECKING THE SHIFT FORKS
1. Check:• Shift fork cam follower “1”
• Shift fork pawl “2”Bends/damage/scoring/wear  Replace the
shift fork.
2. Check: • Shift fork guide barRoll the shift fork guide bar on a flat surface.
Bends  Replace.
EWA
WARNING
Do not attempt to straighten a bent shift fork
guide bar.
3. Check:
• Shift fork movement
(along the shift fork guide bar)
Rough movement  Replace the shift forks
and shift fork guide bar as a set.
1
4 6 2
53
8
7
9

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
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TRANSMISSION
6-80
2. Install:• Collar “1”
• 2nd wheel gear (26T) “2”
• 4th wheel gear (21T) “3”
• 3rd wheel gear (21T) “4”
• 5th wheel gear (21T) “5”
• Collar “6”
• 1st wheel gear (29T) “7”
• O-rings “8” (to the drive axle “9”)
TIP
• Before installation, apply molybdenum disul-fide oil to the inner and end surface of the idler
gear and the collar and to the inner surface of
the sliding gear, then install.
• Apply the lithium-soap-based grease on the
O-ring.
3. Install: • Washer “1”
• Circlip “2”
TIP
• Be sure the circlip sharp-edged corner “a” is positioned opposite side to the washer and
gear “b”.
• Install the circlip with its ends “c” settled even-
ly on the spline crests. 4. Install:
• Collar “1”
TIP
• Apply the lithium-soap-based grease on the oil seal lip.
• When installing the collar into the crankcase, pay careful attention to the crankcase oil seal
lip.
5. Install: • Main axle “1”
• Drive axle “2”
TIP
• Install to the left crankcase simultaneously.
• Apply engine oil to the main axle and the drive
axle bearing.
New
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TRANSMISSION
6-81
6. Install:• Shift fork 1 (L) “1”
• Shift fork 2 (C) “2”
• Shift fork 3 (R) “3”
• Shift cam “4”(to the main axle and the drive axle)
TIP
• Apply engine oil to the shift fork grooves.
• Apply engine oil to the shift cam groove and
the bearing contact surface.
• Mesh the shift fork 1 (L) with the 4th wheel gear “5” and shift fork 3 (R) with the 5th wheel
gear “7” on the drive axle.
• Mesh the shift fork 2 (C) with the 3rd pinion
gear “6” on the main axle. 7. Install:
• Long shift fork guide bar “1”
• Short shift fork guide bar “2”
• Spring “3”
TIP
• Screw the spring into the shift fork guide bar lightly beforehand.
• Apply the engine oil on the shift fork guide
bars.
8. Check: • Operation of shift cam and shift fork
• Transmission operationUnsmooth operation  Repair.
3
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ELECTRIC STARTING SYSTEM
9-8
EAS2GC1362STARTING CIRCUIT CUT-OFF SYSTEM OPERATION
If the meter light comes on, the starter motor can only operate if at least one of the following condi-
tions is met:
• The transmission is in neutral (the neutral switch is closed).
• The clutch lever is pulled to the handlebar (the clutch switch is closed).
The starting circuit cut-off relay prevents the starter motor from operating when neither of these con-
ditions has been met. In this instance, the starting ci rcuit cut-off relay is open so current cannot reach
the starter motor. When at least one of the above conditions has been met the starting circuit cut-off
relay is closed and the engine can be started by pressing the start switch.

ELECTRIC STARTING SYSTEM
9-9
a. WHEN THE TRANSMISSION IS IN NEU-TRAL
b. WHEN THE CLUTCH LEVER IS PULLED TO THE HANDLEBAR
1. Battery
2. Main fuse
3. Main relay
4. Starting circuit cut-off relay
5. Start switch
6. Diode
7. Clutch switch
8. Neutral switch
9. Starter relay
10.Starter motor