General Instruction; Overhaul Of Master Cylinder; Overhauling Of Disc Brake Caliper; Bleeding Operation - Vento Phantom R4i Service Maintenance Manual

GENERAL INSTRUCTION:

1 Never handle brake fluid by bare hands for a longer
time
2 If brake fluid comes in contact with eyes, wash eyes
with cold water and consult a doctor immediately.
3 Never allow brake fluid to come in contact with any
painted parts as it peels off paint. If it happens, wipe
immediately with damp cloth/wash with water.
4 Never clean any hydraulic brake parts with any
mineral oil based cleaner i.e. Kerosene, petrol, or
diesel etc. Always clean all the hydraulic brake
parts only with fresh brake fluid.
5 Never lubricate any components of hydraulic
system with mineral base oil or grease.
6 As the brake fluid is hygroscopic (absorbs moisture
from atmosphere) by nature, it is better to replace the
brake fluid once in a year (After man soon season),
for optimum performance.
7 Whenever any hydraulic brake components are
disconnected perform bleeding operation thoroughly at
reassembly.
8 Do not polish brake pads with sand paper, as hard
particles deposited in the lining may damage steel
disc.
9 Do not use cotton cloth to wipe master cylinder
bore, as rind from cloth will remain in cylinder bore
surface.
10 Always use new rubber seals, boots, washers &
circlip.

OVERHAUL OF MASTER CYLINDER;

1 Remove handle lever screw and left handle lever.
2 Take out stopper anti-dust cover.
3 Remove circlip.
4 Remove piston assy.
Assemble the master cylinder parts in reverse order of
disassembly sequence.
NOTE: Apply brake fluid on master cylinder piston
seals & then insert into the master cylinder body.
VENTO MOTORCYCLES
SPECIFICATION OF VEHICLE PARTS

OVERHAULING OF DISC BRAKE CALIPER

1. Disconnect the brake hose from caliper and collect
the brake fluid, and plug the hole.
2. Loosen the mounting bolts of caliper assay and take
out.
3. Disassemble bolt, braking caliper assy. brake shoe,
and brake shoe spring.
4. Disassemble oil stopper, oil stopper anti-dustcover
and square seal ring. Removal steps are the following:
5. Connect air pressure hose at inlet of the calliper and
apply air pressure, so calliper piston will come out
slowly.
Assemble the disc brake caliper parts in reverse order of
disassembly order.

BLEEDING OPERATION

1 Fill brake fluid reservoir, with fresh recommended
brake fluid (DOT-3 OR DOT-4) up to UPPER LEVEL.
2. Operate brake lever several times to build the
hydraulic pressure in the brake system, keep a watch
on the brake fluid level in the reservoir.
3 Attach a transparent plastic tube to the bleeder valve.
4 Hold the brake lever in applied position, and loosen
the bleeder valve, along with brake fluid air bubbles
will come out through the tube. Tighten the bleeder
valve and then release the brake lever. This
sequence ensures that no fresh air enters into the
system.
5.Repeat the operation as per above step, till the
clear flow of brake fluid comes out through the
transparent tube in between, if required, fill the reservoir
with brake fluid up to "UPPER LEVEL" mark again.
Rev no.01/ page 68of 84