Yamaha MBK MW125 2014, Service Manual

Page: 149 / 380

FRONT BRAKE
4-40
EAS30168
INTRODUCTION
WARNING
EWA14101
Disc brake components rarely require disas-
sembly. Therefore, always follow these pre-
ventive measures:
• Never disassemble brake components un-
less absolutely necessary.
• If any connection on the hydraulic brake
system is disconnected, the entire brake
system must be disassembled, drained,
cleaned, properly filled, and bled after reas-
sembly.
• Never use solvents on internal brake com-
ponents.
• Use only clean or new brake fluid for clean-
ing brake components.
• Brake fluid may damage painted surfaces
and plastic parts. Therefore, always clean
up any spilt brake fluid immediately.
• Avoid brake fluid coming into contact with
the eyes as it can cause serious injury.
FIRST AID FOR BRAKE FLUID ENTERING
THE EYES:
• Flush with water for 15 minutes and get im-
mediate medical attention.
EAS30169
CHECKING THE FRONT BRAKE DISCS
The following procedure applies to both of the
brake discs.
1. Remove:
• Front wheel
Refer to “FRONT WHEELS” on page 4-25.
2. Check:
• Brake disc
Damage/galling
→
Replace.
3. Measure:
• Brake disc runout
Out of specification
→
Correct the brake disc
runout or replace the brake disc.
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a. Place the vehicle on a suitable stand so that
the front wheel is elevated.
b. Before measuring the front brake disc runout,
turn the handlebar to the left or right to ensure
that the front wheel is stationary.
c. Remove the brake caliper.
d. Hold the dial gauge at a right angle against
the brake disc surface.
e. Measure the runout 1.5 mm (0.06 in) below
the edge of the brake disc.
▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲ ▲▲▲ ▲ ▲▲▲
4. Measure:
• Brake disc thickness
Measure the brake disc thickness at a few dif-
ferent locations.
Out of specification
→
Replace.
5. Adjust:
• Brake disc runout
▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼ ▼▼▼ ▼ ▼▼▼
a. Remove the brake disc.
b. Rotate the brake disc by one bolt hole.
c. Install the brake disc.
TIP
Tighten the brake disc bolts in stages.
d. Measure the brake disc runout.
e. If out of specification, repeat the adjustment
steps until the brake disc runout is within
specification.
Brake disc runout limit (as mea-
sured on wheel)
0.15 mm (0.0059 in)
Brake disc thickness limit
3.0 mm (0.12 in)
T
R
.
.
Front brake disc bolt
23 Nm (2.3 m·kgf, 17 ft·lbf)
LOCTITE®