2000 YAMAHA TTR125 engine

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ENGCDI MAGNETO
EC4L0000
CDI MAGNETO
Extent of removal:1 CDI magneto removal
Extent of removal Order Part name Q’ty Remarks
CDI MAGNETO REMOVAL
Preparation for removal Seat and fuel tank Refer to “SAET, FUEL TANK AND SIDE
COVERS” section.
Drain the engine oil Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.
Drive sprocket cover Refer to “ENGINE REMOVAL” section.
1 CDI magneto lead 1
2 Left crankcase cover 1
3 Nut (rotor) 1
Use special tool.
Refer to “REMOVAL POINTS”.
4 Rotor 1
5 Woodruff key 1
6 Pickup coil 1
7 Lead guide 1
8Stator
1
1

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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.
Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.

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ENGENGINE REMOVAL
Extent of removal Order Part name Q’ty Remarks
1 Drive sprocket cover 1
2 Bolt (drive sprocket) 2
Refer to “REMOVAL POINTS”. 3 Drive sprocket holder 1
4 Drive sprocket 1
5 Shift pedal link 1
6 Crankcase breather hose 1
7 Engine bracket (upper) 1
8 Engine skidplate 1
9 Engine bracket (front) 1
10 Engine mounting bolt (rear) 2
11Engine
1Refer to “REMOVAL POINTS”.
1

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ENGENGINE REMOVAL
REMOVAL POINTS
Drive sprocket
1. Remove:
lBolt (drive sprocket)
lDrive sprocket holder 1
lDrive sprocket 2
lDrive chain 3
NOTE:
Remove the drive sprocket together with the
drive chain.
Engine removal
1. Remove:
lEngine 1
From left side.
NOTE:
Make sure that the couplers, hoses and cables
are disconnected.
ASSEMBLY AND INSTALLATION
Engine installation
1. Install:
lEngine 1
Install the engine from left side.
lEngine mounting bolt (rear) 2
lEngine bracket (front) 3
lBolt (engine bracket) 4
lEngine mounting bolt (lower) 5
lEngine mounting bolt (front) 6
lEngine bracket (upper) 7
lBolt (engine bracket) 8
lEngine mounting bolt (upper) 9
T R..40 Nm (4.0 m · kg, 29 ft · lb)
T R..40 Nm (4.0 m · kg, 29 ft · lb)
T R..40 Nm (4.0 m · kg, 29 ft · lb)
T R..40 Nm (4.0 m · kg, 29 ft · lb)
T R..40 Nm (4.0 m · kg, 29 ft · lb)
T R..40 Nm (4.0 m · kg, 29 ft · lb)

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ENGENGINE REMOVAL
NOTE:
Apply the lithium soap base grease on the
thread of the engine mounting bolts (rear) 2.
Shift pedal link
1. Install:
lShift pedal link 1
lBolt (shift pedal link) 2
NOTE:
Adjust the center a of the front end of the shift
pedal to match the highest point of the foot-
rest.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
Drive sprocket
1. Install:
lDrive sprocket 1
lDrive chain 2
NOTE:
Install the drive sprocket together with the
drive chain.
2. Install:
lDrive sprocket holder 1
lBolt (drive sprocket)
T R..6 Nm (0.6 m · kg, 4.3 ft · lb)
3. Install:
lDrive sprocket cover 1
lBolt (drive sprocket cover)
T R..12 Nm (1.2 m · kg, 8.7 ft · lb)

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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 and stator Refer to “CDI MAGNETO” section.

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ENGCRANKCASE, CRANKSHAFT AND BALANCER
REMOVAL POINTS
Crankcase
1. Remove:
lBolt (crankcase)
lLead guide 1
lClutch 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:
lRight crankcase 1
Use the crankcase separating tool 2.
NOTE:
lFully 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.
lAs 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-01135-A/90890-01135

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ENGCRANKCASE, CRANKSHAFT AND BALANCER
Crankcase
1. Inspect:
lContacting surface a
Scratches ® Replace.
lEngine mounting boss b, crankcase
Cracks/damage ® Replace.
2. Inspect:
lBearing
Rotate inner race with a finger.
Rough spot/seizure ® Replace.
Crankshaft
1. Measure:
lRunout limit a
lConnecting rod big end side clearance
b
lCrank width c
Out of specification ® Replace.
Use the dial gauge and a thickness
gauge.
Dial gauge and stand:
YU-03097/90890-01252
Standard
Runout
limit:—0.03 mm
(0.0012 in)
Side
clearance:0.15 ~ 0.45 mm
(0.0059 ~ 0.0177 in)0.50 mm
(0.02 in)
Crack
width:46.95 ~ 47.00 mm
(1.848 ~ 1.850 in)—