Yamaha 2003 YFZ450S, Service Manual

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CHK
ADJ
BLEEDING THE HYDRAULIC BRAKE SYSTEM
NOTE:
_
• Be careful not to spill any brake fluid or allow
the brake master cylinder reservoir or brake
fluid reservoir to overflow.
• When bleeding the hydraulic brake system,
make sure there is always enough brake
fluid before applying the brake. Ignoring this
precaution could allow air to enter the
hydraulic brake system, considerably length-
ening the bleeding procedure.
• If bleeding is difficult, it may be necessary to
let the brake fluid settle for a few hours.
Repeat the bleeding procedure when the tiny
bubbles in the hose have disappeared.
1. Bleed:
• hydraulic brake system
▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼
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 a clear plastic hose
1
tightly to the
bleed screw
2
.
È
Front
É
Rear
d. Place the other end of the hose into a con-
tainer.
e. Slowly apply the brake lever or brake pedal
several times.
f. Fully squeeze the brake lever or fully
depress the brake pedal and hold it in posi-
tion.
g. Loosen the bleed screw.
NOTE:
_
Loosening the bleed screw will release the
pressure 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.
1
2
È
É