2012 YAMAHA YZ450F clutch

4-46
ENGINE REMOVAL
REMOVING THE ENGINE
Order Part name Q'ty Remarks
Hold the machine by placing the suitable stand
under the frame.Refer to "HANDLING NOTE".
Throttle body Refer to "THROTTLE BODY" section in the
CHAPRE 6.
Rear fenderRefer to "SEAT AND SIDE COVERS" sec-
tion.
Exhaust pipe and silencer Refer to "EXHAUST PIPE AND SILENCER"
section.
Clutch cable Disconnect at the engine side.
Shift pedalRefer to "KICK SHAFT AND SHIFT SHAFT"
section.
Cylinder head breather hose Refer to "CAMSHAFTS" section.
Drain the engine oil.Refer to "CHANGING THE ENGINE OIL"
section in the CHAPTER 3.
Engine guard (Right)
1 Drive chain sprocket cover 1
2 Nut (drive sprocket) 1 Refer to removal section.
3 Lock washer 1 Refer to removal section.
4 Drive sprocket 1 Refer to removal section.

4-53
CRANKCASE AND CRANKSHAFT
DISASSEMBLING THE
CRANKCASE
1. Separate:
• Right crankcase
• Left crankcase
Separation steps:
a. Remove the crankcase bolts,
hose guide and clutch cable hold-
er.
Loosen each bolt 1/4 of a turn at a
time and after all the bolts are loos-
ened, remove them.
b. Remove the right crankcase "1".
• Place the crankcase with its left
side downward and split it by insert-
ing a screwdriver tip into the split-
ting slit "a" in the crankcase.
• Lift the right crankcase horizontally
while lightly patting the case split-
ting slit and engine mounting boss
using a soft hammer, and leave the
crankshaft and transmission with
the left crankcase.
Use soft hammer to tap on the
case half. Tap only on reinforced
portions of case. Do not tap on
gasket mating surface. Work slow-
ly 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.
REMOVING THE BALANCER
SHAFT
1. Remove:
• Balancer shaft "1"
Remove the balancer shaft with its
flat side "a" facing the crankshaft.
REMOVING THE CRANKSHAFT
1. Remove:
• Crankshaft "1"
Use the crankcase separating
tool "2".
• Install the crankcase separating
tool as shown.
• Do not use a hammer to drive out
the crankshaft.
REMOVING THE CRANKCASE
BEARING
1. Remove:
• Bearing "1"
• Remove the bearing from the
crankcase by pressing its inner
race.
• Do not use the removed bearing.
CHECKING THE TIMING CHAIN
AND TIMING CHAIN GUIDE
1. Inspect:
• Timing chain
Cracks/stiff→Replace the timing
chain and camshaft sprocket as a
set.
2. Inspect:
• Timing chain guide
Wear/damage→Replace.
CHECKING THE CRANKCASE
1. Inspect:
• Contacting surface "a"
Scratches → Replace.
• Engine mounting boss "b", crank-
case
Cracks/damage → Replace.
2. Inspect:
• Bearing
Rotate inner race with a finger.
Rough spot/seizure → Replace.
Crankcase separating
tool:
YU-A9642/90890-04152

5-24
HANDLEBAR
HANDLEBAR
REMOVING THE HANDLEBAR
Order Part name Q'ty Remarks
Number plate Remove the band only.
1 Clutch cable 1 Disconnect at the lever side.
2 Clutch lever holder 1
3 Engine stop switch 1
4 Brake master cylinder 1 Refer to removal section.
5 Throttle cable cap 1
6 Throttle cable #1 (pulled) 1 Disconnect at the throttle side.
7 Throttle cable #2 (pushed) 1 Disconnect at the throttle side.
8 Right grip 1 Refer to removal section.
9 Tube guide 1
10 Collar 1
11 Left grip 1 Refer to removal section.
12 Handlebar upper holder 2
13 Handlebar 1
14 Handlebar lower holder 2
15 Cap 1

5-27
HANDLEBAR
11. Install:
• Engine stop switch "1"
• Clutch lever holder "2"
• Bolt (clutch lever holder) "3"
•Clamp "4"
• The engine stop switch, clutch lever
holder and clamp should be in-
stalled according to the dimensions
shown.
• Pass the engine stop switch lead in
the middle of the clutch lever hold-
er.
12. Install:
• Clutch cable "1"
Apply the lithium soap base grease
on the clutch cable end.
13. Adjust:
• Clutch lever free play
Refer to "ADJUSTING THE
CLUTCH CABLE FREE PLAY"
section in the CHAPTER 3.Bolt (clutch lever holder):
5 Nm (0.5 m•kg, 3.6
ft•lb)
0 mm
0 mm