Yamaha Wr250r 2008 Manual

 
FRONT BRAKE 
4-11 
EAS22210 
FRONT BRAKE 
Removing the front brake pads
Order Job/Parts to remove Q’ty Remarks  
1 Pin plug 1 WR250X only
2 Front brake caliper support bolt 1
3 Front brake caliper assembly 1
4 Brake pad 2
5 Brake pad spring 2
For installation, reverse the removal proce-
dure.
1 2
23
45S
S
WR250X
T R..23 Nm (2.3 m • kg, 17 ft • Ib) 
T R..17 Nm (1.7 m • kg, 12 ft • Ib) 
T R..17 Nm (1.7 m • kg, 12 ft • Ib) 
T R..2.5 Nm (0.25 m • kg, 1.8 ft • Ib)  

 
FRONT BRAKE 
4-12 
Removing the front brake master cylinder
Order Job/Parts to remove Q’ty Remarks  
Brake fluidDrain.
Refer to“BLEEDING THE HYDRAULIC 
BRAKE SYSTEM” on page 1-25.
1 Rear view mirror (right) 1
2 Brake lever 1
3 Front brake switch 1
4 Union bolt 1
5 Copper washer 2
6 Front brake hose 1
7 Brake master cylinder reservoir cap 1
8Brake master cylinder reservoir diaphragm 
holder1
9 Brake master cylinder reservoir diaphragm 1
10 Front brake master cylinder holder 1
11 Front brake master...

 
FRONT BRAKE 
4-13 
Disassembling the front brake master cylinder
Order Job/Parts to remove Q’ty Remarks  
1 Master cylinder kit 1
For assembly, reverse the disassembly pro-
cedure.
1 

 
FRONT BRAKE 
4-14 
Removing the front brake calipers
Order Job/Parts to remove Q’ty Remarks  
Brake fluidDrain.
Refer to“BLEEDING THE HYDRAULIC 
BRAKE SYSTEM” on page 1-25.
1 Brake hose holder 1
2 Union bolt 1
3 Copper washer 2
4 Front brake hose 1
5 Pin plug 1 Only WR250X
6 Front brake caliper support bolt 1
7 Brake pad 2
8 Brake pad spring 2
9 Front brake caliper assembly 1
10 Front brake caliper bracket 1
For installation, reverse the removal proce-
dure.
S
56
69
78
101
4
S
2
3
T R..2.5 Nm (0.25 m •...

 
FRONT BRAKE 
4-15 
Disassembling the front brake calipers
Order Job/Parts to remove Q’ty Remarks  
1 Brake caliper piston 2
2 Brake caliper dust seal 2
3 Brake caliper piston seal 2
4 Bleed screw 1
For assembly, reverse the disassembly pro-
cedure.
12
34
S
S
BF
BF
T R..6 Nm (0.6 m • kg, 4.3 ft • Ib)  

 
FRONT BRAKE 
4-16 
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...

 
FRONT BRAKE 
4-17 
d. Measure the brake disc deflection.
e. If out of specification, repeat the adjustment
steps until the brake disc deflection is within
specification.
f. If the brake disc deflection cannot be brought
within specification, replace the brake disc.

 
6. Install: 
 
Front wheel
Refer to “FRONT WHEEL” on page 4-2. 
EAS22280 
REPLACING THE FRONT BRAKE PADS
NOTE:
 
When replacing the brake pads, it is not neces-
sary to disconnect the brake hose or...

 
FRONT BRAKE 
4-18 
4. Check: 
 
Brake fluid level
Below the minimum level mark “a”  
→ 
 Add the
recommended brake fluid to the proper level.
Refer to “CHECKING THE BRAKE FLUID
LEVEL” on page 1-23.
5. Check: 
 
Brake lever free play
Refer to “ADJUSTING THE FRONT DISC
BRAKE” on page 1-22. 
 
Brake pedal operation
Soft or spongy feeling  
→ 
 Bleed the brake
system.
Refer to “BLEEDING THE HYDRAULIC
BRAKE SYSTEM” on page 1-25. 
EAS22290 
REMOVING THE FRONT BRAKE CALIPER
NOTE:
 
Before disassembling the...

 
FRONT BRAKE 
4-19 
 
Brake caliper cylinders “2”
Scratches/wear  
→ 
 Replace the brake caliper
assembly. 
 
Brake caliper body “3”
Cracks/damage  
→ 
 Replace the brake caliper
assembly. 
 
Brake fluid delivery passages
(brake caliper body)
Obstruction  
→ 
 Blow out with compressed air.
WARNING
 
EWA13600  
Whenever a brake caliper is disassembled, 
replace the piston seals. 
2. Check: 
 
Brake caliper bracket
Cracks/damage  
→ 
 Replace. 
EAS22400 
ASSEMBLING THE FRONT BRAKE CALIPER
WARNING...

 
FRONT BRAKE 
4-20 
brake performance. 
 
Refill with the same type of brake fluid that
is already in the system. Mixing brake flu-
ids may result in a harmful chemical reac-
tion, 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.
CAUTION:
 
 ECA13540 
Brake fluid may damage painted surfaces
and plastic parts. Therefore, always clean up...