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4 - 64
ENG
3. Install the starter clutch 1 on the rotor 2.
NOTE:
Install the starter clutch with its plate portion
a facing the rotor.
Insert the plate portion of the starter clutch
so that it is flush with the surface of contact
b with the rotor.
12 b
a
4. Tighten:
Bolt (starter clutch)
NOTE:
Caulk a the end of the starter clutch holding
bolt near its outer diameter to serve as a stop-
per.
a
T R..30 Nm (3.0 m · kg, 22 ft · lb)
5. Install:
Starter wheel gear 1
Woodruff key 2
Rotor 3
NOTE:
Clean the tapered portion of the crankshaft
and the magneto hub.
When installing the magneto rotor, make
sure the woodruff key is properly seated in
the key way of the crankshaft.
Apply the engine oil on the starter wheel
gear inner circumference.
6. Install:
Plain washer 1
Nut (magneto) 2
NOTE:
Tighten the nut (magneto) while holding the
magneto with a sheave holder 3.
Sheave holder:
YS-1880-A/90890-01701
2
1
3
E
T R..80 Nm (8.0 m · kg, 58 ft · lb)
CDI MAGNETO AND STARTER CLUTCH
(TT-R125E/TT-R125LWE)
Page 388 of 610
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ENG
7. Install:
Crankcase cover (left)
8. Connect:
Neutral switch lead 1
NOTE:
Pass the neutral switch lead into the crank-
case cover groove as shown.
9. Connect:
CDI magneto lead
Refer to “CABLE ROUTING DIAGRAM”
section in the CHAPTER 2.
CDI MAGNETO AND STARTER CLUTCH
(TT-R125E/TT-R125LWE)
Page 390 of 610
4 - 66
ENGENGINE REMOVAL
ENGINE REMOVAL
Extent of removal:1 Engine removal
Extent of removal Order Part name Q’ty Remarks
ENGINE REMOVAL
Preparation for removal Hold the machine by placing the
suitable stand under the frame.
Seat, fuel tank and side covers Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Carburetor Refer to “CARBURETOR” section.
Muffler Refer to “MUFFLER” section.
Clutch cable Disconnect at engine side.
Spark plug cap
Disconnect the CDI magneto
lead.
Disconnect the neutral switch lead
for the TT-R125E/TT-R125LWE.
Starter motor for the TT-R125E/
TT-R125LWERefer to “ELECTRIC STARTING SYS-
TEM” section in the CHAPTER 6 for the
TT-R125E/TT-R125LWE.
Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.
Page 398 of 610
4 - 70
ENGCRANKCASE, CRANKSHAFT AND BALANCER
CRANKCASE, CRANKSHAFT AND BALANCER
Extent of removal:1 Crankcase separation2 Balancer removal
3 Crankshaft removal
Extent of removal Order Part name Q’ty Remarks
CRANKCASE, CRANKSHAFT
AND BALANCER REMOVAL
Preparation for removal Engine Refer to “ENGINE REMOVAL” section.
Piston Refer to “CYLINDER AND PISTON” sec-
tion.
Primary drive gear Refer to “CLUTCH AND PRIMARY
DRIVEN GEAR” section.
Kick axle assembly
Refer to “KICK AXLE AND SHIFT
SHAFT” section.
Segment
Rotor for the TT-R125/
TT-R125LWRefer to “CDI MAGNETO” section for the
TT-R125/TT-R125LW.
(Rotor and starter clutch for the
TT-R125E/TT-R125LWE)(Refer to “CDI MAGNETO AND
STARTER CLUTCH” section for the
TT-R125E/TT-R125LWE.)
Page 400 of 610
4 - 71
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
REMOVAL POINTS
Crankcase
1. Remove:
Bolt (crankcase)
Lead guide 1
Clutch cable holder 2
NOTE:
Loosen each bolt 1/4 of a turn at a time and
after all the bolts are loosened, remove them.
2. Remove:
Right crankcase 1
Use the crankcase separating tool 2.
NOTE:
Fully tighten the tool holding bolts, but make
sure the tool body is parallel with the case. If
necessary, one screw may be backed out
slightly to level tool body.
As pressure is applied, alternately tap on the
front engine mounting boss and transmission
shafts.
CAUTION:
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 one end “hangs
up”, take pressure off the push screw, re-
align, and start over. If the cases do not
separate, check for a remaining case screw
or fitting. Do not force.
Crankcase separating tool:
YU-1135-A/90890-01135
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4 - 77
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
Page 508 of 610
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CHASHANDLEBAR
EC5B0000
HANDLEBAR
TT-R125
Extent of removal:1 Handlebar removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalHANDLEBAR REMOVAL
Number plate
1 Clutch cable 1
2 Clutch lever 1
3 Engine stop switch 1
4 Front brake cable 1
5 Front brake lever 1
6 Grip cap (lower) 1
7 Grip cap (upper) 1
8 Throttle cable 1
9 Throttle grip assembly 1
10 Collar 1
11 Handlebar grip (left) 1 Refer to “REMOVAL POINTS”.
12 Handlebar holder 2
13 Handlebar 1
1