Bleeding The Hydraulic Brake System - Yamaha XT250X Service Manual

Direction "a"
Brake light comes on sooner.
Direction "b"
Brake light comes on later.
a
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EAS21350
BLEEDING THE HYDRAULIC BRAKE
SYSTEM
EWA13100
WARNING
Bleed the hydraulic brake system whenever:
the system is disassembled.
G
a brake hose is loosened, disconnected or
G
replaced.
the brake fluid level is very low.
G
brake operation is faulty.
G
1. Remove:
Brake master cylinder reservoir cap
G
NOTE:
Be careful not to spill any brake fluid or allow
G
the brake master cylinder reservoir to overflow.
When bleeding the hydraulic brake system,
G
make sure there is always enough brake fluid
before applying the brake. Ignoring this pre-
caution could allow air to enter the hydraulic
brake system, considerably lengthening the
bleeding procedure.
If bleeding is difficult, it may be necessary to let
G
the brake fluid settle for a few hours. Repeat
the bleeding procedure when the tiny bubbles
in the hose have disappeared.
2. Bleed:
Hydraulic brake system
G
MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
a. Fill the brake fluid reservoir to the proper level
with the recommended brake fluid.
b. Install the diaphragm (brake master cylinder
reservoir or brake fluid reservoir).
c. Connect clear plastic hose "1" tightly to bleed
1
b
2
3-19
screw "2", and place an oil pan under the
plastic hose end.
A
2
B
A. Front
B. Rear
d. Place the other end of the hose into a con-
tainer.
e. Slowly apply the brake several times.
f. Fully pull the brake lever or fully press down
the brake pedal and hold it in position.
g. Loosen the bleed screw.
NOTE:
Loosening the bleed screw will release the pres-
sure and cause the brake lever to contact the
throttle grip or the brake pedal to fully extend.
h. Tighten the bleed screw and then release the
brake lever or brake pedal.
i. Repeat steps (e) to (h) until all of the air bub-
bles have disappeared from the brake fluid in
the plastic hose.
j. Tighten the bleed screw to specification.
Bleed screw
6 Nm (0.6 m•kg, 4.3 ft•lb)
k. Fill the brake fluid reservoir to the proper level
with the recommended brake fluid.
Refer to "CHECKING THE BRAKE FLUID
LEVEL" on page 3-19.
EWA13110
WARNING
After bleeding the hydraulic brake system,
CHASSIS
1
2
1