Advertisement
8 . 6
Brakes, wheels and tyres
attaching the hose. With the hose attached,
the valve can then be opened and closed with
an open-ended spanner.
6 Check the fluid level in the reservoir. Do not
allow the fluid level to drop below the half-way
mark on the inspection window during the
procedure (see illustration).
7 Carefully pump the brake lever three or four
times and hold it in while opening the caliper
bleed valve. When the valve is opened, brake
fluid will flow out of the caliper into the clear
hose and the lever will move toward the
handlebar.
8 Tighten the bleed valve, then release the
brake lever gradually. Repeat the process until
no air bubbles are visible in the brake fluid
leaving the caliper and the lever is firm when
applied. On completion, disconnect the hose,
then tighten the bleed valve and fit the dust cap.
9 Top-up the reservoir, install the diaphragm,
diaphragm plate and cover, and wipe up any
spilled brake fluid. Check the entire system for
fluid leaks.
I f it
i s not possible to produce
a firm feel to the lever the
HINT
fluid m y b e aerated. Let the
brake fluid in the system
stabilise for a few hours and then repeat
the ptucedure when the tiny bubbles in
the system have settled out.
Fluid change
10 Changing the brake fluid is a similar
process to bleeding the brakes and requires
the same materials plus a suitable syringe for
emptying the hydraulic reservoir and back-
filling the system with fluid.
11 Remove the reservoir cover, diaphragm
plate and diaphragm and siphon the old fluid out
of the reservoir. Temporarily refit the reservoir
cover but do not tighten the fixing screws.
12 Remove the brake caliper and slowly push
the pistons as far back into the caliper as
possible using hand pressure or a piece of
wood for leverage, then siphon any residual
8.6 Check the fluid level
fluid from the reservoir. Refit the brake caliper.
Leave the cover off the reservoir.
13 Fill the syringe with approximately 40 ml of
new brake fluid and connect a short length of
hose to the syringe. Bleed any air from the
syringe and hose, then connect the hose to the
caliper bleed valve. Note: To avoid damaging
the bleed valve during the procedure, loosen it
and then tighten i t temporarily with a ring
spanner before attaching the hose. With the
hose attached, the valve can then be opened
and closed with an open-ended spanner.
14 Open the bleed valve and carefully inject
fluid into the system until the level in the
reservoir is up to the half-way mark on the
inspection window. Tighten the bleed valve,
disconnect the hose and refit the dust cap.
15 Operate the brake lever carefully several
times to bring the pads into contact with the
disc, then check the fluid level in the reservoir
and top-up if necessary (see Daily (pre-ride)
checks).
much darker in colour than
see when a l l o l d fluid has
been expelled from the system.
16 Install the diaphragm, diaphragm plate
and cover, and wipe up any spilled brake
fluid. Check the system for fluid leaks.
17 Check the operation of the brakes before
riding the scooter.
9 Rear drum brake
-
inspection and shoe renewal
Q Q
\
Warning: The dust created by the
brake
system
may
contain
asbestos, which i s harmful to your
health. Never blow
it
out with compressed
air and don'f inhale any o f it. An approved
filtering mask should b e worn when
working on the brakes.
Inspection
1 Remove the wheel (see Section 15).
2 Check the condition of the friction material
on the brake shoes (see illustration). No
minimum thickness specification is given, but
if the wear indicator aligns with the index mark
when the brake is applied, the shoes should
be renewed.
3 Inspect the friction material for contamination.
If it is fouled with oil or grease, or heavily scored
or damaged, both shoes must be renewed as a
set. Note that it is not possible to degrease the
friction material; if the shoes are contaminated in
any way they must be renewed.
4 If the shoes are in good condition, clean
them carefully using a fine wire brush which is
completely free of oil and grease to remove all
traces of dust and corrosion.
5 Check the condition of the brake shoe
springs; they should hold the shoes tightly in
place against the operating cam and pivot
post (see illustration 9.2). Remove the shoes
(see Steps 10 to 12) and renew the springs if
they appear weak or are obviously deformed
or damaged.
6 Clean the brake drum surface using
acetone or brake system cleaner. Examine the
surface for scoring and excessive wear (see
illustration). While light scratches are to be
expected, heavy score marks will impair
braking and there is no satisfactory way of
9.2 Check the friction material (A) and springs (B)
9.6 Check the surface of the brake drum (arrowed)
Advertisement
