wheel YAMAHA TTR125 2003 Owner's Manual

3 - 27
INSP
ADJTIRE PRESSURE CHECK/SPOKES INSPECTION AND
TIGHTENING/WHEEL INSPECTION
EC36Q000
TIRE PRESSURE CHECK
1. Measure:
Tire pressure
Out of specification → Adjust.
NOTE:
Check the tire while it is cold.
Loose bead stoppers allow the tire to slip off
its position on the rim when the tire pressure
is low.
A tilted tire valve stem indicates that the tire
slips off its position on the rim.
If the tire valve stem is found tilted, the tire is
considered to be slipping off its position. Cor-
rect the tire position.
Standard tire pressure:
100 kPa (1.00 kgf/cm2, 15 psi)
SPOKES INSPECTION AND TIGHTENING
1. Inspect:
Spokes 1
Bend/damage → Replace.
Loose spoke → Retighten.
2. Tighten:
Spokes
NOTE:
Be sure to retighten these spokes before and
after break-in. After a practice check spokes
for looseness.
T R..Front 2 Nm (0.2 m · kg, 1.4 ft · lb)
Rear 3 Nm (0.3 m · kg, 2.2 ft · lb)
EC36T000
WHEEL INSPECTION
1. Inspect:
Wheel runout
Elevate the wheel and turn it.
Abnormal runout → Replace.

3 - 28
INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
2. Inspect:
Bearing free play
Exist play → Replace.
STEERING HEAD INSPECTION AND
ADJUSTMENT
1. Elevate the front wheel by placing a suit-
able stand under the engine.
2. Check:
Steering shaft
Grasp the bottom of the forks and gen-
tly rock the fork assembly back and
forth.
Free play → Adjust steering head.
3. Check:
Steering smooth action
Turn the handlebar lock to lock.
Unsmooth action → Adjust steering ring
nut.
4. Adjust:
Steering ring nut
Steering ring nut adjustment steps:
Remove the number plate and starter
knob.
Remove the main switch, handlebar and
upper bracket.
Remove the special washer 1
Remove the upper ring nut 2, and rubber
washer 3.
Loosen the lower ring nut 4 using the
steering nut wrench 5.
Steering nut wrench:
YU-33975/90890-01403

4 - 58
ENGCDI MAGNETO AND STARTER CLUTCH
CDI MAGNETO AND STARTER CLUTCH
Extent of removal:1 Pickup coil/stator removal2 Starter clutch/wheel gear removal
Extent of removal Order Part name Q’ty Remarks
CDI MAGNETO AND STATOR
REMOVAL
Preparation for removal Fuel tank
1 CDI magneto lead 1
2 Neutral switch lead 1
3 Left crankcase cover 1
4 Nut (rotor) 1
Use special tool.
Refer to “REMOVAL POINTS”.
5 Rotor 1
6 Starter clutch 1
7 Woodruff key 1
8 Starter wheel gear 1
9 Plain washer 1
10 Plate (starter idle gear) 1
11 Starter idle gear 1
12 Lead guide 1
13Pickup coil/stator assembly
1
1
2
1
1

4 - 59
ENGCDI MAGNETO AND STARTER CLUTCH
REMOVAL POINTS
Rotor
1. Remove:
Nut (rotor) 1
Plain washer 2
Use the sheave holder 3.
Sheave holder:
YS-1880-A/90890-01701
2. Remove:
Rotor 1
Use the flywheel puller 2.
Flywheel puller:
YU-33270-B/90890-01362
EC4L4000
INSPECTION
EC4L4101
CDI magneto
1. Inspect:
Rotor inner surface a
Stator outer surface b
Damage → Inspect the crankshaft
runout and crankshaft bearing.
If necessary, replace CDI magneto and/
or stator.
EC4L4200
Woodruff key
1. Inspect:
Woodruff key 1
Damage → Replace.
Starter clutch
1. Check:
Starter clutch
Damage/wear → Replace.
2. Check:
Idle gear
Starter clutch gear
Pitting/burrs/chips/roughness/wear →
Replace the defective parts.

4 - 61
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. Tighten:

Nut (magneto)
1

NOTE:

Tighten the nut (magneto)
1
while holding the
magneto
2
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

4 - 78
ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
Transmission
1. Install:
4th pinion gear (22T) 1
3rd pinion gear (19T) 2
2nd pinion gear (18T) 3
5th pinion gear (24T) 4
On main axle 5.
NOTE:
Apply the molybdenum disulfide oil on the
gears’ inner circumference.
Install the 5th pinion gear so that measure-
ment a is 83.25 ~ 83.45 mm (3.278 ~
3.285 in).
2. Install:
2nd wheel gear (32T) 1
5th wheel gear (21T) 2
3rd wheel gear (25T) 3
4th wheel gear (23T) 4
1st wheel gear (37T) 5
On drive axle 6.
NOTE:
Apply the molybdenum disulfide oil on the
gears’ inner circumference.

4 - 80
ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
Shift cam and shift fork
1. Install:
Shift fork 1 (L) 1
Shift fork 2 (C) 2
Shift fork 3 (R) 3
NOTE:
Mesh the shift fork #1 (L) with the 2nd wheel
gear and #3 (R) with the 4th wheel gear on
the drive axle.
Mesh the shift fork #2 (C) with the 3rd pinion
gear on the main axle.
2. Install:
Shift cam 1
NOTE:
Apply the engine oil on the shift cam.
3. Install:
Shift fork guide bar 1 (short) 1
Shift fork guide bar 2 (long) 2
NOTE:
Apply the engine oil on the guide bars.
Be sure the long bar is inserted into the shift
forks #1 and #3 and the short one into #2.
4. Check:
Shifter operation
Transmission operation
Unsmooth operation → Repair.

5 - 1
CHAS

FRONT WHEEL AND FRONT BRAKE (TT-R125E)
EC500000
CHASSIS
FRONT WHEEL AND FRONT BRAKE (TT-R125E)
Extent of removal:
1
Front wheel removal
2
Wheel bearing removal
3
Brake shoe plate assembly removal and disassembly
Extent of removal Order Part name Q’ty Remarks
Preparation for removal
FRONT WHEEL AND DRUM
BRAKE
Hold the machine by placing the
suitable stand under the engine.
WARNING

Support the machine securely so there is no
danger of it falling over.
1 Brake cable holder 1
2 Brake cable 1 Disconnect at the lever side, first.
3 Axle nut 1
4 Wheel axle 1
5 Front wheel 1
6 Collar set 1
7 Brake shoe plate assembly 1
8 Oil seal 1
9 Wheel bearing 2 Refer to “REMOVAL POINTS”.
10Spacer
1
2
3
1

5 - 2
CHAS

FRONT WHEEL AND FRONT BRAKE (TT-R125E)
Extent of removal Order Part name Q’ty Remarks
11 Brake shoe 2
12 Spring 2
13 Brake camshaft lever 1
14 Wear indicator plate 1
15 Brake camshaft 1
16 Brake shoe plate 1
3

5 - 3
CHAS

FRONT WHEEL AND FRONT BRAKE (TT-R125E)
REMOVAL POINTS
EC513201
Wheel bearing (if necessary)
1. Remove:

Bearing
1

NOTE:

Remove the bearing using a general bearing
puller
2
.
INSPECTION
EC514100
Wheel
1. Measure:

Wheel runout
Out of limit
→
Repair/replace.
Wheel runout limit:
Radial
1
: 2.0 mm (0.08 in)
Lateral
2
: 2.0 mm (0.08 in)
2. Inspect:

Bearing
Rotate inner race with a finger.
Rough spot/seizure
→
Replace.
NOTE:

Replace the bearings, oil seal and wheel collar
as a set.
EC514200
Wheel axle
1. Measure:

Wheel axle bends
Out of specification
→
Replace.
Use the dial gauge
1
.
NOTE:

The bending value is shown by one half of the
dial gauge reading.
WARNING

Do not attempt to straighten a bent axle.
Wheel axle bending limit:
0.5 mm (0.020 in)