Timing YAMAHA TTR125 2003 User Guide

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ENG

CYLINDER AND PISTON
CYLINDER AND PISTON
Extent of removal:
1
Cylinder removal
2
Piston removal
Extent of removal Order Part name Q’ty Remarks
CYLINDER AND PISTON
REMOVAL
Preparation for removal Cylinder head Refer to “CYLINDER HEAD” section.
1 Exhaust timing chain guide 1
2 Cylinder/O-ring 1/1
3 Dowel pin 2
4 Gasket 1
5 Piston pin clip 2
Refer to “REMOVAL POINTS”. 6 Piston pin 1
7 Piston 1
8Piston ring set
1
1
2

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ENGCYLINDER AND PISTON
Cylinder
1. Install:
Dowel pins 1
Gasket (cylinder) 2 New
2. Install:
O-ring
Cylinder 1
Exhaust timing chain guide
CAUTION:
Install the cylinder with one hand while
compressing the piston rings with the
other hand.
Pass the timing chain through the cylin-
der timing chain cavity.
Be careful not to damage the timing chain
guide during installation.
NOTE:
After installing, check the smooth movement of
the piston.
New

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ENGCRANKCASE, CRANKSHAFT AND BALANCER
Extent of removal Order Part name Q’ty Remarks
1 Intake timing chain guide 1
2 Timing chain 1
3 Bolt [45 mm (1.8 in)] 7
4 Bolt [55 mm (2.2 in)] 1
5 Bolt [30 mm (1.2 in)] 2
6 Lead guide 1
7 Clutch cable holder 1
8 Right crankcase 1
Use special tool.
Refer to “REMOVAL POINTS”.
9 Left crankcase 1
10 Balancer 1
11 Crankshaft 1 Use special tool.
Refer to “REMOVAL POINTS”.
12 Bearing 3 Refer to “REMOVAL POINTS”.
3
21

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ENGCRANKCASE, CRANKSHAFT AND BALANCER
Crankshaft
1. Remove:
Crankshaft 1
Use the crankcase separating tool 2.
CAUTION:
Do not use a hammer to drive out the
crankshaft.
Crankcase separating tool:
YU-1135-A/90890-01135
Bearing
1. Remove:
Bearing 1
NOTE:
Remove the bearing from the crankcase by
pressing its inner race as shown in.
Do not use the removed bearing.
INSPECTION
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.

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ENGCRANKCASE, CRANKSHAFT AND BALANCER
3. Tighten:
Lead guide 1
Clutch cable holder 2
Bolt (crankcase) [45 mm (1.8 in)] 3
Bolt (crankcase) [55 mm (2.2 in)] 4
Bolt (crankcase) [30 mm (1.2 in)] 5
NOTE:
Apply Quick gasket® (YAMAHA Bond
No.1215) on end of the crankcase bolts [45
mm (1.8 in)] 3, as shown.
Tighten the crankcase bolts in stage, using a
crisscross pattern.
Quick gasket®:
ACC-QUICK-GS-KT
YAMAHA Bond No.1215:
90890-85505
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
4. Check:
Crankshaft and transmission operation
Unsmooth operation → Repair.
5. Install:
Timing chain 1
Intake timing chain guide 2
Bolt (intake timing chain guide)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)LT