2003 YAMAHA TTR125 air bleeding

3 - 15
INSP
ADJ
EC360000
CHASSIS
EC361012
BRAKE SYSTEM AIR BLEEDING (TT-R125LW)
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 bleed.
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)

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INSP
ADJ
4. Inspect:
Brake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section in the CHAP-
TER 3.
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)
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)

5 - 22
CHAS
Brake fluid
1. Fill:
Brake fluid
Until the fluid level reaches “LOWER”
level line a.
WARNING
Use only the designated quality brake
fluid:
otherwise, the rubber seals may deterio-
rate, causing leakage and poor brake per-
formance.
Refill with the same type of brake fluid;
mixing fluids may result in a harmful chem-
ical reaction and lead to poor performance.
Be 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:
Brake system
Refer to “BRAKE SYSTEM AIR
BLEEDING” section in the CHAPTER
3.
3. Inspect:
Brake fluid level
Fluid at lower level → Fill up.
Refer to “BRAKE FLUID LEVEL
INSPECTION” section in the CHAP-
TER 3.
FRONT BRAKE (TT-R125LW)