Chapter Eleven - Yamaha MM700A Manual

This chapter covers service procedures for the hydrauli-
cally activated disc brake system and the mechanically
Refer to Chapter Three for brake adjustment and brake
fluid level and filling procedures.
The handlebar control lever applies the disc brake.
When the lever is pulled in hydraulic force is applied to
the caliper. The caliper piston forces the pads against the
jackshaft mounted brake disc, slowing the vehicle. As the
pads wear, the piston moves out of the caliper to automati-
cally compensate for wear. This gradual repositioning of
the piston causes the fluid level in the reservoir to drop.
Check the reservoir level frequently and add DOT 4 brake
fluid as required.
Rotating the parking brake lever on the handlebar brake
lever engages the chainease mounted parking brake cali-
per.
Brake Service
Observe the following when servicing the disc brake.
1 When working on hydraulic brake systems, it is neces-
sary that the work area and all tools be absolutely clean.
Any tiny particles of dirt and debris in the hydraulic sys-
tem can damage the components.

Chapter Eleven

Brakes
2. Use only DOT 4 brake fluid from a sealed container.
3. Do not allow disc brake fluid to contact any plastic
parts or painted surfaces, as damage will result.
4. Always keep the master cylinder reservoir and spare
cans of brake fluid closed to prevent dust or moisture from
entering. This results in brake fluid contamination and
brake problems.
clean any internal brake components with solvent or with
any other petroleum-based cleaners. Solvents cause the
seals to swell and distort, which require replacing the
seals.
6. Whenever any component, other than the reservoir
cap, has been removed from the brake system the system
is considered opened and must be bled to remove air bub-
bles. Also, if the brake feels spongy, this usually means
there are air bubbles in the system and it must be bled. For
safe brake operation, refer to Bleeding the System in this
chapter.
Do not intermix silicone based (DOT
because it can cause brake corn-
fluid
we.
5 )