2001 YAMAHA TTR125 wheel

3 - 3
INSP
ADJ

PRE-OPERATION INSPECTION AND MAINTENANCE
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation or practice, make sure the machine is in good operating condi-
tion.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-12
Engine oilCheck that the oil level is correct. Check the crankcase for leak-
age.P.3-7 ~ 10
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-4
Throttle grip/housingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-4 ~ 5
BrakesCheck the play of front and rear brake and effect of front and
rear brake.
Check fluid level and leakage. (TT-R125LW only)P.3-15 ~ 20
Drive chainCheck chain slack and alignment. Check that the chain is lubri-
cated properly.P.3-21 ~ 22
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-24 ~ 25
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-25 ~ 27
Front forks and rear shock
absorber assemblyCheck that they operate smoothly and there is no oil leakage. P.3-23 ~ 24
Cables (wires)Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or
when the front forks travel up and down.—
Muffler Check that the muffler is tightly mounted and has no cracks. P.4-2
Sprocket Check that the driven sprocket tightening nut is not loose. P.3-20
Lubrication Check for smooth operation. Lubricate if necessary. P.3-28
Bolts and nuts Check the chassis and engine for loose bolts and nuts. —
Lead connectorsCheck that the CDI magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-5

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INSP
ADJ
4. Inspect:
lBrake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section in the CHAP-
TER 3.
5. Check:
lBrake lever operation
A softy or spongy feeling ® Bleed
brake system.
Refer to “BRAKE SYSTEM AIR
BLEEDING” section.
FRONT BRAKE SHOE INSPECTION (TT-R125)
1. Inspect:
lBrake shoe lining wear limit
lConnect the transparent hose 4 to the
bleed screw 5 and place the suitable con-
tainer under its end.
lLoosen the bleed screw and push the
brake caliper piston in.
CAUTION:
Do not reuse the drained brake fluid.
lTighten the bleed screw.
T R..
Bleed screw:
6 Nm (0.6 m • kg, 4.3 ft • lb)
lInstall the brake caliper 6 and brake cali-
per support bolt 7.
NOTE:
Apply the lithium soap base grease on the
caliper support bolt.
T R..
Brake caliper support bolt:
22 Nm (2.2 m • kg, 16 ft • lb)
Brake shoe lining wear limit checking
steps:
lFully pull in the brake lever and hold it in
position.
lThen check the brake shoe wear indicator
1 is within the wear limit a.
Outside the limit ® Replace the brake
shoe.
Refer to “FRONT WHEEL AND FRONT
BRAKE” section in the CHAPTER 5.
FRONT BRAKE SHOE INSPECTION (TT-R125)

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INSP
ADJ
REAR BRAKE SHOE INSPECTION
1. Inspect:
lBrake shoe lining wear limit
BRAKE FLUID LEVEL INSPECTION
(TT-R125LW)
1. Place the brake master cylinder so that
its top is in a horizontal position.
2. Inspect:
lBrake fluid level
Fluid at lower level ® Fill up.
aLower level
WARNING
lUse only designated quality brake fluid to
avoid poor brake performance.
lRefill with same type and brand of brake
fluid; mixing fluids could result in poor
brake performance.
lBe sure that water or other contaminants
do not enter brake master cylinder when
refilling.
lClean up spilled fluid immediately to
avoid erosion of painted surfaces or plas-
tic parts. Brake shoe lining wear limit checking
steps:
lFully push down the brake pedal and hold
it in position.
lThen check the brake shoe wear indicator
1 is within the wear limit a.
Outside the limit ® Replace the brake
shoe.
Refer to “REAR WHEEL AND REAR BRAKE”
section in the CHAPTER 5.
Recommended brake fluid:
DOT #4
SPROCKETS INSPECTION
1. Inspect:
lSprocket teeth a
Excessive wear ® Replace.
NOTE:
Replace the drive, driven sprockets and drive
chain as a set.
REAR BRAKE SHOE INSPECTION/BRAKE FLUID LEVEL
INSPECTION (TT-R125LW)/SPROCKETS INSPECTION

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INSPADJ
DRIVE CHAIN SLACK ADJUSTMENT
6. Lubricate:
lDrive chain
Drive chain lubricant:
SAE 10W-30 motor oil or suit-
able chain lubricants
DRIVE CHAIN SLACK ADJUSTMENT
1. Elevate the rear wheel by placing the suitable stand under the engine.
2. Check:
lDrive chain slack a
In the center between the drive axle
and rear wheel axle.
Out of specification ® Adjust.
NOTE:
Before checking and/or adjusting, rotate the
rear wheel through several revolutions and
check the slack several times to find the tight-
est point. Check and/or adjust chain slack with
rear wheel in this “tight chain” position.
Drive chain slack:
35 ~ 50 mm (1.4 ~ 2.0 in)
3. Adjust:
lDrive chain slack
Drive chain slack adjustment steps:
lLoosen the axle nut 1.
lTurn both drive chain pullers 2 the same
amount a and adjust them to the stopper
in the same position so that the drive
chain slack is within the specified limits.
CAUTION:
Too small chain slack will overload the
engine and other vital parts; keep the
slack within the specified limits.
lTighten the axle nut while pushing down
the drive chain.
T R..
Axle nut: 60 Nm (6.0 m • kg, 43 ft • lb)

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INSP
ADJFRONT FORK INSPECTION/
REAR SHOCK ABSORBER ASSEMBLY INSPECTION/
REAR SHOCK ABSORBER SPRING PRELOAD ADJUSTMENT
EC36C000
FRONT FORK INSPECTION
1. Inspect:
lFront fork smooth action
Operate the front brake and stroke the
front fork.
Unsmooth action/oil leakage ® Repair
or replace.
REAR SHOCK ABSORBER ASSEMBLY
INSPECTION
1. Inspect:
lSwingarm smooth action
Abnormal noise/unsmooth action ®
Grease the pivoting points or repair the
pivoting points.
Damage/oil leakage ® Replace.
REAR SHOCK ABSORBER SPRING
PRELOAD ADJUSTMENT
1. Elevate the rear wheel by placing the
suitable stand under the engine.
2. Remove:
lLeft side cover
3. Loosen:
lLocknut 1
4. Adjust:
lSpring preload
By turning the adjuster 2.
Stiffer ®Increase the spring preload.
(Turn the adjuster 2 in.)
Softer ®Decrease the spring preload.
(Turn the adjuster 2 out.)
Spring length (installed) a:
Standard length Extent of adjustment
165 mm
(6.50 in)155 ~ 175 mm
(6.10 ~ 6.89 in)

3 - 25
INSP
ADJSPOKES INSPECTION AND TIGHTENING/WHEEL INSPECTION/
STEERING HEAD INSPECTION AND ADJUSTMENT
SPOKES INSPECTION AND TIGHTENING
1. Inspect:
lSpokes 1
Bend/damage ® Replace.
Loose spoke ® Retighten.
2. Tighten:
lSpokes
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:
lWheel runout
Elevate the wheel and turn it.
Abnormal runout ® Replace.
2. Inspect:
lBearing 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:
lSteering shaft
Grasp the bottom of the forks and gen-
tly rock the fork assembly back and
forth.
Free play ® Adjust steering head.

4 - 59
ENGCDI MAGNETO
REMOVAL POINTS
Rotor
1. Remove:
lNut (rotor) 1
lPlain washer 2
Use the sheave holder 3.
Sheave holder:
YS-1880-A/90890-01701
2. Remove:
lRotor 1
Use the flywheel puller 2.
Flywheel puller:
YU-33270-B/90890-01362
EC4L4000
INSPECTION
EC4L4101
CDI magneto
1. Inspect:
lRotor inner surface a
lStator outer surface b
Damage ® Inspect the crankshaft
runout and crankshaft bearing.
If necessary, replace CDI magneto and/
or stator.
EC4L4200
Woodruff key
1. Inspect:
lWoodruff key 1
Damage ® Replace.
EC4L5000
ASSEMBLY AND INSTALLATION
CDI magneto
1. Install:
lStator 1
lBolt (stator)
lLead guide
lScrew (lead guide) 2
lPickup coil 3
lBolt (pickup coil)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)LT
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)LT
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)LT

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ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
Transmission
1. Install:
l4th pinion gear (22T) 1
l3rd pinion gear (19T) 2
l2nd pinion gear (18T) 3
l5th pinion gear (24T) 4
On main axle 5.
NOTE:
lApply the molybdenum disulfide oil on the
gears’ inner circumference.
lInstall the 5th pinion gear so that measure-
ment a is 83.25 ~ 83.45 mm (3.278 ~
3.285 in).
2. Install:
l2nd wheel gear (32T) 1
l5th wheel gear (21T) 2
l3rd wheel gear (25T) 3
l4th wheel gear (23T) 4
l1st wheel gear (37T) 5
On drive axle 6.
NOTE:
Apply the molybdenum disulfide oil on the
gears’ inner circumference.