warning YAMAHA TTR125 2002 Owner's Manual

5 - 15
CHAS
Brake caliper piston seal kit
1. Remove:
lBrake caliper dust seal 1
lBrake caliper piston seal 2
NOTE:
Remove the brake caliper piston seals and
brake caliper dust seals by pushing them with
a finger.
CAUTION:
Never attempt to pry out brake caliper pis-
ton seals and brake caliper dust seals.
WARNING
Replace the brake caliper piston seals and
brake caliper dust seals whenever a brake
caliper is disassembled.
INSPECTION
Brake master cylinder
1. Inspect:
lBrake master cylinder inner surface a
Wear/scratches ® Replace brake mas-
ter cylinder assembly.
Stains ® Clean.
WARNING
Use only new brake fluid.
2. Inspect:
lDiaphragm 1
Crack/damage ® Replace.
3. Inspect:
lBrake master cylinder piston 1
lBrake master cylinder cup 2
Wear/damage/score marks ® Replace
brake master cylinder kit.
FRONT BRAKE (TT-R125LW)

5 - 16
CHAS
Brake caliper
1. Inspect:
lBrake caliper cylinder inner surface a
Wear/score marks ® Replace brake
caliper assembly.
2. Inspect:
lBrake caliper piston 1
Wear/score marks ® Replace brake
caliper piston assembly.
WARNING
Replace the brake caliper piston seals and
brake caliper dust seals 2 whenever a
brake caliper is disassembled.
3. Inspect:
lBrake caliper bracket 1
Cracks/damage ® Replace the brake
caliper assembly.
lGuide pin 2
Rust/damage ® Replace the brake cal-
iper assembly.
lSleeve boot 3
lPin boot 4
Wear/damage ® Replace.
4. Inspect:
lBrake caliper support bolt 1
Scorches/rust/damage ® Replace.
Brake hose
1. Inspect:
lBrake hose 1
Crack/damage ® Replace.
FRONT BRAKE (TT-R125LW)

5 - 17
CHASFRONT BRAKE (TT-R125LW)
ASSEMBLY AND INSTALLATION
WARNING
lAll internal parts should be cleaned in
new brake fluid only.
lInternal parts should be lubricated with
brake fluid when installed.
lReplace the brake caliper piston seals
and brake caliper dust seals whenever a
brake caliper is disassembled.
Brake caliper piston
1. Clean:
lBrake caliper
lBrake caliper piston seal
lBrake caliper dust seal
lBrake caliper piston
Clean them with brake fluid.
2. Install:
lBrake caliper piston seal 1
lBrake caliper dust seal 2
WARNING
Always use new brake caliper piston seals
and brake caliper dust seals.
NOTE:
Fit the brake caliper piston seals and brake
caliper dust seals onto the slot on brake cali-
per correctly.
New
New
3. Install:
lBrake caliper piston 1
NOTE:
Apply the brake fluid on the brake caliper pis-
ton wall.
CAUTION:
lInstall the brake caliper piston with its
shallow depressed side a facing the
brake caliper.
lNever force to insert.
Brake caliper
1. Install:
lSleeve boot 1.
On brake caliper bracket 2.

5 - 19
CHASFRONT BRAKE (TT-R125LW)
2. Install:
lBrake master cylinder cup (primary) 1
lBrake master cylinder cup (secondary) 2
On brake master cylinder piston 3.
NOTE:
Apply the brake fluid on the brake master cyl-
inder cup.
WARNING
After installing, cylinder cup should be
installed as shown direction. Wrong instal-
lation cause improper brake performance.
3. Install:
lSpring 1
On brake master cylinder piston 2.
NOTE:
Install the spring at the smaller diameter side.
4. Install:
lBrake master cylinder kit 1
lWasher 2
lCirclip 3
lBrake master cylinder boot 4
On brake master cylinder 5
NOTE:
lApply the brake fluid on the brake master
cylinder kit.
lWhen installing the circlip, use a long nose
circlip pliers.

5 - 20
CHAS
Brake master cylinder
1. Install:
lBrake master cylinder 1
lBrake master cylinder bracket 2
lBolt (brake master cylinder bracket) 3
NOTE:
lInstall the brake master cylinder bracket so
that the arrow mark a face upward.
lFirst tighten the bolts on the upper side of the
brake master cylinder bracket, and then
tighten the bolts on the lower side.
2. Install:
lBrake lever 1
lSpring 2
lBolt (brake lever) 3
lNut (brake lever) 4
NOTE:
lApply the lithium soap base grease on the
bolt and brake lever sliding surface.
lApply the molybdenum disulfide grease on
the tip of the adjuster bolt.
T R..9 Nm (0.9 m · kg, 6.5 ft · lb)
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
Brake hose
1. Install:
lCopper washer 1
lBrake hose 2
lUnion bolt 3
WARNING
Always use new copper washers.
CAUTION:
Install the brake hose so that its pipe por-
tion a directs as show and lightly touches
the projection b on the brake caliper.
New
T R..26 Nm (2.6 m · kg, 19 ft · lb)
FRONT BRAKE (TT-R125LW)

5 - 21
CHAS
2. Pass the brake hose through the cable
guide 1.
3. Install:
lCopper washer 1
lJoint 2
lBrake hose 3
WARNING
Always use a new copper washer.
NOTE:
When turning the joint over the brake hose,
hold the brake hose so that it may not be
twisted.
New
T R..26 Nm (2.6 m · kg, 19 ft · lb)
T R..14 Nm (1.4 m · kg, 10 ft · lb)
4. Install:
lBrake hose holder 1
lBolt (brake hose holder ) 2
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
FRONT BRAKE (TT-R125LW)

5 - 22
CHAS
Brake fluid
1. Fill:
lBrake fluid
Until the fluid level reaches “LOWER”
level line a.
WARNING
lUse only the designated quality brake
fluid:
otherwise, the rubber seals may deterio-
rate, causing leakage and poor brake per-
formance.
lRefill with the same type of brake fluid;
mixing fluids may result in a harmful chem-
ical reaction and lead to poor performance.
lBe careful that water does not enter the
brake master cylinder when refilling.
Water will significantly lower the boiling
point of the fluid and may result in vapor
lock.
CAUTION:
Brake fluid may erode painted surfaces or
plastic parts. Always clean up spilled fluid
immediately.
Recommended brake fluid:
DOT #4
2. Air bleed:
lBrake system
Refer to “BRAKE SYSTEM AIR
BLEEDING” section in the CHAPTER
3.
3. Inspect:
lBrake fluid level
Fluid at lower level ® Fill up.
Refer to “BRAKE FLUID LEVEL
INSPECTION” section in the CHAP-
TER 3.
FRONT BRAKE (TT-R125LW)

5 - 24
CHAS
REAR WHEEL AND REAR BRAKE
Extent of removal:1 Rear 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 removalREAR WHEEL AND DRUM
BRAKE
Hold the machine by placing the
suitable stand under the engine.
WARNING
Support the machine securely so there is nodanger of it falling over.
1 Brake rod 1
2 Axle nut 1
3 Drive chain puller (right) 1
4 Wheel axle 1
5 Drive chain puller (left) 1
6 Drive chain 1
7 Rear wheel 1 Refer to “REMOVAL POINTS”.
8 Collar (right) 1
9 Brake shoe plate assembly 1
10Collar (left)
1
231
REAR WHEEL AND REAR BRAKE

5 - 27
CHASREAR WHEEL AND REAR BRAKE
NOTE:
The bending value is shown by one half of the
dial gauge reading.
WARNING
Do not attempt to straighten a bent axle.
Drum brake
1. Inspect:
lBrake shoe lining surface
Glazed areas ® Polish.
Use coarse sand paper.
NOTE:
After polishing, wipe the polished particles with
a cloth.
2. Measure:
lBrake shoe lining thickness a
Out of specification ® Replace.
NOTE:
Replace the brake shoes and springs as a set
if either is worn to the limit.
Brake shoe lining thickness:
Standard
4.0 mm
(0.16 in)2.0 mm
(0.08 in)
3. Measure:
lBrake drum inside diameter a
Out of specification ® Replace.
Brake drum inside diameter:
Standard
110 mm
(4.33 in)111 mm
(4.37 in)

5 - 29
CHASREAR WHEEL AND REAR BRAKE
5. Install:
lSprings 1
lBrake shoes 2
On brake shoe plate 3
NOTE:
lApply the lithium soap base grease on the
pivot pin.
lWhen installing the springs and brake shoes,
take care not to damage the springs.
lWhen replacing the brake shoes, replace the
springs as a set.
WARNING
Do not apply grease to the brake shoe lin-
ings.
New
Rear wheel
1. Install:
lWheel bearing 1
lSpacer 2
lWheel bearing 3
lOil seal 4
NOTE:
lApply the lithium soap base grease on the oil
seal lip when installing.
lInstall the bearing with seal facing outward.
lUse a socket that matches the outside diam-
eter of the race of the bearing.
lRight side of bearing shall be installed first.
lInstall the oil seal with its manufacture’s
marks or numbers facing outward.
CAUTION:
Do not strike the inner race of the bearing.
Contact should be made only with the outer
race.
New