Page 182 of 616

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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/TT-R125LWE 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.3-27 ~ 28
SteeringCheck that the handlebar can be turned smoothly and have no 
excessive play.P.3-28 ~ 32
Front forks and rear shock 
absorber assemblyCheck that they operate smoothly and there is no oil leakage. P.3-23 ~ 26
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.3-33
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:
Brake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
5. Check:
Brake lever operation
A softy or spongy feeling → Bleed
brake system.
Refer to “BRAKE SYSTEM AIR
BLEEDING” section.
FRONT BRAKE SHOE INSPECTION 
(TT-R125/TT-R125E)
1. Inspect:
Brake shoe lining wear limit
Connect the transparent hose 4 to the
bleed screw 5 and place the suitable con-
tainer under its end.
Loosen the bleed screw and push the
brake caliper piston in.
CAUTION:
Do not reuse the drained brake fluid.
Tighten the bleed screw.
T R..
Bleed screw:
6 Nm (0.6 m • kg, 4.3 ft • lb)
Install 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:
Fully pull in the brake lever and hold it in
position.
Then 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/TT-R125E) 
     
        
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INSP
ADJ
REAR BRAKE SHOE INSPECTION
1. Inspect:
Brake shoe lining wear limit
BRAKE FLUID LEVEL INSPECTION
(TT-R125LW/TT-R125LWE)
1. Place the brake master cylinder so that
its top is in a horizontal position.
2. Inspect:
Brake fluid level
Fluid at lower level → Fill up.
aLower level
WARNING
Use only designated quality brake fluid to
avoid poor brake performance.
Refill with same type and brand of brake
fluid; mixing fluids could result in poor
brake performance.
Be sure that water or other contaminants
do not enter brake master cylinder when
refilling.
Clean up spilled fluid immediately to
avoid erosion of painted surfaces or plas-
tic parts. Brake shoe lining wear limit checking
steps:
Fully push down the brake pedal and hold
it in position.
Then 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:
Sprocket 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/TT-R125LWE)/SPROCKETS INSPECTION 
     
        
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INSP
ADJ
DRIVE CHAIN SLACK ADJUSTMENT
6. Lubricate:
Drive 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:
Drive 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:
Drive chain slack
Drive chain slack adjustment steps:
Loosen the axle nut 1.
Turn 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.
Tighten 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
ADJ
REAR SHOCK ABSORBER ASSEMBLY 
INSPECTION
1. Inspect:
Swingarm 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:
Left side cover
3. Loosen:
Locknut 1 
4. Adjust:
Spring preload
By turning the adjuster 2.
NOTE:
Be sure to remove all dirt and mud from
around the locknut and adjuster before
adjustment.
The length of the spring (installed) changes
1.5 mm (0.06 in) per turn of the adjuster.
CAUTION:
Never attempt to turn the adjuster beyond
the maximum or minimum setting.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
TT-R125/TT-R125E/
TT-R125LW:
165 mm 
(6.50 in)
TT-R125LWE:
160.5 mm 
(6.32 in)TT-R125/TT-R125E/
TT-R125LW:
155 ~ 175 mm 
(6.10 ~ 6.89 in)
TT-R125LWE:
147.5 ~ 167.5 mm
(5.81 ~ 6.59 in)
REAR SHOCK ABSORBER ASSEMBLY INSPECTION/
REAR SHOCK ABSORBER SPRING PRELOAD ADJUSTMENT 
     
        
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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. 
     
        
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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:
TT-R125/TT-R125LW
Steering ring nut
Steering ring nut adjustment steps:
Remove the number plate and starter
knob.
Remove the 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 
     
        
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ENG
REMOVAL POINTS
Rotor
1. Remove:
Nut (rotor) 1 
Plain washer 2 
Use the sheave holder 3.
2. Remove:
Rotor 1 
Use the flywheel puller 2.
Sheave holder:
YS-1880-A/90890-01701
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.
EC4L5000
ASSEMBLY AND INSTALLATION
CDI magneto
1. Install:
Stator 1 
Bolt (stator)
Lead guide
Screw (lead guide) 2 
Pickup coil 3 
Bolt (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
CDI MAGNETO (TT-R125/TT-R125LW)