Suzuki VLR1800, Service Manual

Page: 497 / 624

Brake Control System and Diagnosis: 4A-5
Brake Fluid Level Check
B822H14106005
Refer to “Brake System Inspection in Section 0B
(Page 0B-18)”.
Brake Hose Inspection
B822H14106006
Refer to “Brake System Inspection in Section 0B
(Page 0B-18)”.
Air Bleeding from Brake Fluid Circuit
B822H14106007
Air trapped in the brake fluid circuit acts like a cushion to
absorb a large proportion of the pressure developed by
the master cylinder and thus interferes with the full
braking performance of the brake caliper. The presence
of air is indicated by “sponginess” of the brake lever and
also by lack of braking force. Considering the danger to
which such trapped air exposes the machine and rider, it
is essential that after remounting the brake and restoring
the brake system to the normal condition, the brake fluid
circuit be purged of air in the following manner:
CAUTION
!
Handle brake fluid with care: the fluid reacts
chemically with paint, plastic, rubber
materials, etc.
Front Brake
1) Fill the master cylinder reservoir to the top of the
inspection window. Place the reservoir cap to
prevent dirt from entering.
2) Attach a clear hose to the air bleeder valve, and
insert the free end of the hose into a receptacle.
3) Squeeze and release the brake lever several times
in rapid succession and squeeze the lever fully
without releasing it.
4) Loosen the air bleeder valve by turning it a quarter of
a turn so that the brake fluid runs into the receptacle,
this will remove the tension of the brake lever
causing it to touch the handlebar grip.
5) Close the air bleeder valve, pump and squeeze the
lever, and open the valve.
6) Repeat this process until the fluid flowing into the
receptacle no longer contains air bubbles.
NOTE
While bleeding the brake system, replenish
the brake fluid in the reservoir as necessary.
Make sure that there is always some fluid
visible in the reservoir.
7) Close the air bleeder valve and disconnect the hose.
Tightening torque
Front brake caliper air bleeder valve: 6 N·m (0.6
kgf-m, 4.5 lb-ft)
I822H1410004-01
I822H1410005-01
I822H1410006-01