Removing The Front Brake Master Cylinder; Checking The Front Brake Master Cylinder - Yamaha MBK MW125 2014 Service Manual

Specified brake fluid
YAMAHA GENUINE BRAKE
FLUID (DOT 4)
EWA13540
WARNING
• Use only the designated brake fluid. Other
brake fluids may cause the rubber seals to
deteriorate, causing leakage and poor
brake performance.
• Refill with the same type of brake fluid that
is already in the system. Mixing brake fluids
may result in a harmful chemical reaction,
leading to poor brake performance.
• When refilling, be careful that water does
not enter the brake master cylinder reser-
voir. Water will significantly lower the boil-
ing point of the brake fluid and could cause
vapor lock.
ECA13540
NOTICE
Brake fluid may damage painted surfaces
and plastic parts. Therefore, always clean up
any spilt brake fluid immediately.
5. Bleed:
• Brake system
Refer to "BLEEDING THE HYDRAULIC
BRAKE SYSTEM" on page 3-12.
6. Check:
• Brake fluid level
Below the minimum level mark "a" → Add the
specified brake fluid to the proper level.
Refer to "BLEEDING THE HYDRAULIC
BRAKE SYSTEM" on page 3-12.
a
7. Check:
• Brake lever operation
Soft or spongy feeling → Bleed the brake sys-
tem.
Refer to "BLEEDING THE HYDRAULIC
BRAKE SYSTEM" on page 3-12.
EAS30179
REMOVING THE FRONT BRAKE MASTER
CYLINDER
TIP
Before removing the front brake master cylinder,
drain the brake fluid from the entire brake sys-
tem.
1. Remove:
• Brake hose union bolt "1"
• Copper washers "2"
• Front brake hose "3"
TIP
To collect any remaining brake fluid, place a
container under the master cylinder and the end
of the brake hose.
3
EAS30725
CHECKING THE FRONT BRAKE MASTER
CYLINDER
1. Check:
• Brake master cylinder
Damage/scratches/wear → Replace.
• Brake fluid delivery passages
(brake master cylinder body)
Obstruction → Blow out with compressed air.
2. Check:
• Brake master cylinder kit
Damage/scratches/wear → Replace.
3. Check:
• Brake master cylinder reservoir cap
• Brake master cylinder reservoir diaphragm
holder
• Brake master cylinder reservoir diaphragm
Damage/wear → Replace.
4. Check:
• Front brake hose
Cracks/damage/wear → Replace.
4-44
FRONT BRAKE
2
1