Page 93 of 610

SPEC
2 - 20
MAINTENANCE SPECIFICATIONS
Drive chain:
Type/manufacturer DID428HD/DAIDO ----
Number of links 122 links ----
Chain slack 35 ~ 50 mm (1.4 ~ 2.0 in) ----
Chain length (10 links) ----121.4 mm
(4.78 in)
Front disc brake:
Disc outside dia. × Thickness 220 × 3.0 mm (8.66 × 0.12 in)220 × 2.5 mm
(8.66 × 0.10 in)
Deflection limit ----0.15 mm (0.006 in)
Pad thickness 4.0 mm (0.16 in)0.8 mm (0.03 in)
Master cylinder inside dia. 11.0 mm (0.433 in) ----
Caliper cylinder inside dia. 22.22 mm (0.875 in) × 2 ----
Brake fluid type DOT #4 ----
Rear drum brake:
Drum brake type Leading, trailing ----
Drum inside diameter 110 mm (4.33 in) 111 mm (4.37 in)
Lining thickness 4.0 mm (0.16 in) 2.0 mm (0.08 in)
Shoe spring free length 50.5 mm (1.99 in) ----
Brake lever and brake pedal:
Brake lever free play (lever end) 2 ~ 5 mm (0.08 ~ 0.20 in) ----
Brake pedal position
(vertical height below footrest top)1 mm (0.04 in) ----
Brake pedal free play 20 ~ 30 mm (0.79 ~ 1.18 in) ----
Clutch lever free play (lever end) 10 ~ 15 mm (0.39 ~ 0.59 in) ----
Throttle grip free play 3 ~ 5 mm (0.12 ~ 0.20 in) ----Item Standard Limit
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INSP
ADJ
MAINTENANCE INTERVALS
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind
that such factors as weather, terrain, geographical location, and individual usage will alter the
required maintenance and lubrication intervals. If you are a doubt as to what intervals to follow in
maintaining and lubricating your machine, consult your Yamaha dealer.
Dealer
NoteItem Checks and maintenance jobsInitial Every
10 hours
(1 month)60 hours
(6 months)120 hours
(12 months)
*Fuel lineCheck fuel hoses for cracks or damage.
Replace if necessary.
Spark plugCheck condition.
Clean, regap or replace if necessary.
*ValvesCheck valve clearance.
Adjust if necessary.
Air filter Clean or replace element if necessary.
*CarburetorCheck engine idling speed and starter operation.
Adjust if necessary.
Exhaust systemsCheck for leakage.
Retighten if necessary.
Replace gasket if necessary.
Engine oilCheck oil level and vehicle for oil leakage.
Correct if necessary.
Change. (Warm engine before draining.)
ClutchCheck operation.
Adjust or replace cable.
*Front brakeCheck operation.
Adjust brake lever free play.
Check fluid level and leakage.
(TT-R125LW/TT-R125LWE only)Every ride
*Rear brakeCheck operation.
Adjust brake pedal free play and replace brake
shoes if necessary.Every ride
*WheelsCheck balance, runout, spoke tightness and for
damage.
Tighten spokes and rebalance, replace if
necessary.
*TiresCheck tread depth and for damage.
Replace if necessary.
Check air pressure.
Correct if necessary.
*Wheel bearingsCheck bearing for looseness or damage.
Replace if necessary.
*SwingarmCheck swingarm pivoting point for play.
Correct if necessary.
Lubricate with molybdenum disulfide grease.
Drive chainCheck chain slack.
Adjust if necessary. Make sure that the rear wheel
is properly aligned.
Clean and lubricate.Every ride
*Steering bearingsCheck bearing play and steering for roughness.
Correct accordingly.
Lubricate with lithium soap base grease every 120
hours.
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INSP
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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
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EC360000
CHASSIS
EC361012
BRAKE SYSTEM AIR BLEEDING
(TT-R125LW/TT-R125LWE)
WARNING
Bleed the brake system if:
The system has been disassembled.
A brake hose has been loosened or
removed.
The brake fluid is very low.
The brake operation is faulty.
A dangerous loss of braking performance
may occur if the brake system is not prop-
erly bled.
1. Remove:
Brake master cylinder cap
Diaphragm
2. Bleed:
Brake fluid
Air bleeding steps:
a. Add proper brake fluid to the reservoir.
b. Install the diaphragm. Be careful not to
spill any fluid or allow the reservoir to
overflow.
c. Connect the clear plastic tube 2 tightly
to the caliper bleed screw 1.
d. Place the other end of the tube into a
container.
e. Slowly apply the brake lever several
times.
f. Pull in the lever. Hold the lever in posi-
tion.
g. Loosen the bleed screw and allow the
lever to travel towards its limit.
h. Tighten the bleed screw when the lever
limit has been reached; then release the
lever.
T R..
Bleed screw:
6 Nm (0.6 m • kg, 4.3 ft • lb)
i. Repeat steps (e) to (h) until of the air
bubbles have been removed from the
system.
CHASSIS/BRAKE SYSTEM AIR BLEEDING
(TT-R125LW/TT-R125LWE)
Page 204 of 610
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INSP
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3. Install:
Diaphragm
Brake master cylinder cap
NOTE:
If bleeding is difficult, it may be necessary to
let the brake fluid system stabilize for a few
hours. Repeat the bleeding procedure when
the tiny bubbles in the system have disap-
peared.
j. Add brake fluid to the level line on the
reservoir.
WARNING
Check the operation of the brake after
bleeding the brake system.
FRONT BRAKE ADJUSTMENT
TT-R125/TT-R125E
1. Check:
Brake lever free play a
Out of specification → Adjust.
2. Adjust:
Brake lever free play
NOTE:
For minute adjustment, loosen the locknut 2
on the lever side and adjust with the adjuster
3.
CAUTION:
Make sure that there is no brake drag after
adjusting the brake lever free play.
Brake lever free play a:
10 ~ 15 mm (0.39 ~ 0.59 in)
Brake lever free play adjustment steps:
Loosen the locknuts 1.
Turn the locknuts until free play a is
within the specified limits by changing their
tightening position.
Tighten the locknuts.
FRONT BRAKE ADJUSTMENT
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INSP
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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
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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
Page 448 of 610
5 - 12
CHAS
FRONT BRAKE (TT-R125LW/TT-R125LWE)
Extent of removal:1 Brake hose removal 2 Brake caliper removal
3 Brake master cylinder removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalFRONT BRAKE REMOVAL
Hold the machine by placing the
suitable stand under the engine.
Drain the brake fluid.
WARNINGSupport the machine securely so there is nodanger of it falling over.
Refer to “REMOVAL POINTS”.
1 Brake hose holder 2
2 Union bolt 1
3 Brake hose 1
4 Joint 1
5 Brake caliper support bolt 1
6 Brake caliper 1 Refer to “REMOVAL POINTS”.
7 Brake lever 1
8 Brake master cylinder bracket 1
9Brake master cylinder
1
3
12
2
3
FRONT BRAKE (TT-R125LW/TT-R125LWE)