Yamaha XT250X - Introduction; Checking the Front Brake Disc

FRONT BRAKE
4-17
EAS22220
INTRODUCTION
WARNING
EWA14100
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.
EAS22230
CHECKING THE FRONT BRAKE DISC
1. Remove:
●
Front wheel
Refer to “FRONT WHEEL” on page 4-2.
2. Check:
● Front brake disc
Damage/galling → Replace.
3. Measure:
● Brake disc deflection
Out of specification → Correct the brake disc
deflection 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 deflec-
tion, 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 deflection at the point 13 mm
(front brake) or 14 mm (rear brake) below the
edge of brake disc.
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4. Measure:
● Brake disc thickness
Measure the brake disc thickness at a few dif-
ferent locations.
Out of specification → Replace.
5. Adjust:
● Brake disc deflection
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a. Remove the brake disc.
b. Turn the brake disc by one bolt hole.
c. Install the brake disc.
NOTE:
Tighten the brake disc bolts in stages and in a
crisscross pattern.
Brake disc deflection limit
0.15 mm (0.0059 in)
Brake disc thickness limit
3.0 mm (0.12 in)