Installing The Rear Brake Master Cylinder - Yamaha WR450FN 2022 Owner's Service Manual

• Dust boot "4"
TIP
• Always install new brake master cylinder kit
"5".
• Before installation, apply brake fluid to the
brake master cylinder piston assembly.
• Before installation, apply silicone grease to the
push rod end.
• Before installation, apply brake fluid to the in-
side of the brake master cylinder.
EAM30051
INSTALLING THE REAR BRAKE MASTER
CYLINDER
1. Install:
• Copper washer
New
• Brake hose
• Union bolt
Brake hose union bolt
30 N·m (3.0 kgf·m, 22 lb·ft)
EWA13531
WARNING
Proper brake hose routing is essential to in-
sure safe vehicle operation.
ECA24500
NOTICE
Make sure that the pipe portion of the brake
hose touches the projection "a" on the brake
caliper.
2. Pour brake fluid to the brake fluid reservoir up
to the specified level.
5 New
1
3 4
2
a
4-36
Specified brake fluid
DOT 4
EWA13090
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 fluid reservoir. Water
will significantly lower the boiling point of
the brake fluid and could cause vapor lock.
ECA24510
NOTICE
Brake fluid may damage painted surfaces
and plastic parts. Therefore, always clean up
any spilt brake fluid immediately.
3. Bleed:
• Brake system
Refer to "BLEEDING THE HYDRAULIC
BRAKE SYSTEM" on page 3-25.
4. Check:
• Brake fluid level
The minimum level mark or below  Add.
Refer to "CHECKING THE BRAKE FLUID
LEVEL" on page 3-23.
5. Check:
• Brake pedal operation
A softy or spongy feeling  Bleed the brake
system.
Refer to "BLEEDING THE HYDRAULIC
BRAKE SYSTEM" on page 3-25.
REAR BRAKE