2002 YAMAHA WR 250F brake

5 - 21
CHASFRONT BRAKE AND REAR BRAKE
Brake master cylinder kit
1. Clean:
Brake master cylinder
Brake master cylinder kit
Clean them with brake fluid.
2. Install:
Brake master cylinder cup (primary) 1
Brake master cylinder cup (secondary)
2
To brake master cylinder piston 3.
NOTE:
Apply the brake fluid on the brake master cyl-
inder cup.
WARNING
After installing, cylinder cup should be
installed as shown direction. Wrong instal-
lation cause improper brake performance.
ÅFront
ıRear
Åı
Åı
3. Install:
Spring 1
To brake master cylinder piston 2.
NOTE:
Install the spring at the smaller dia. side.
ÅFront
ıRear
Åı

5 - 22
CHASFRONT BRAKE AND REAR BRAKE
4. Install:
[Front]
Brake master cylinder kit 1
Washer 2
Circlip 3
Brake master cylinder boot 4
To brake master cylinder 5.
[Rear]
Brake master cylinder kit 1
Push rod 2
Circlip 3
Brake master cylinder boot 4
To brake master cylinder 5.
NOTE:
Apply the brake fluid on the brake master
cylinder kit.
Apply the lithium soap base grease on the tip
of the push rod.
When installing the circlip, use a long nose
circlip pliers.
ÅFront
ıRear
Å
ı
Front brake master cylinder
1. Install:
Brake master cylinder 1
Brake master cylinder bracket 2
Bolt (brake master cylinder bracket) 3
NOTE:
Install the bracket so that the arrow mark a
face upward.
First tighten the bolts on the upper side of the
brake master cylinder bracket, and then
tighten the bolts on the lower side.
T R..9 Nm (0.9 m · kg, 6.5 ft · lb)

5 - 23
CHASFRONT BRAKE AND REAR BRAKE
2. Install:
Brake lever 1
Bolt (brake lever) 2
Nut (brake lever) 3
NOTE:
Apply the lithium soap base grease on the
brake lever sliding surface, bolt and contacting
surface of the brake master cylinder piston.
Rear brake master cylinder
1. Install:
Reservoir hose 1
Reservoir tank 2
Bolt (reservoir tank) 3
T R..6 Nm (0.6 m · kg, 4.3 ft · lb)
T R..6 Nm (0.6 m · kg, 4.3 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
2. Install:
Brake master cylinder 1
Bolt (brake master cylinder) 2
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
3. Install:
Spring 1
Brake pedal 2
O-ring 3
Bolt (brake pedal) 4
Clip 5
NOTE:
Apply the lithium soap base grease on the
bolt, O-ring and brake pedal bracket.
Install the clip with its stopper portion a fac-
ing inward.
T R..26 Nm (2.6 m · kg, 19 ft · lb)

5 - 24
CHASFRONT BRAKE AND REAR BRAKE
4. Install:
Pin 1
Washer 2
Cotter pin 3
NOTE:
After installing, check the brake pedal height.
Refer to “REAR BRAKE ADJUSTMENT” sec-
tion in the CHAPTER 3.
Front brake hose
1. Install:
Brake hose 1
To brake hose holder 2.
NOTE:
Before tightening the bolt (brake hose holder),
pass the brake hose in front of the axle boss
a, then fit it into the hose groove b so that the
brake hose does not contact the nut (wheel
axle).
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
2. Install:
Brake hose cover 1
Washer 2
Bolt [brake hose cover (M8)] 3
Bolt [brake hose cover (M6)] 4
T R..16 Nm (1.6 m · kg, 11 ft · lb)
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
3. Pass the brake hose through the cable
guides 1, then through the guides a on
the protector 2.

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CHASFRONT BRAKE AND REAR BRAKE
4. Install:
Copper washer 1
Brake hose 2
Union bolt 3
WARNING
Always use new copper washers.
CAUTION:
Install the brake hose so that it contacts
the master cylinder projection a and that
its bent portion b faces downward.
T R..30 Nm (3.0 m · kg, 22 ft · lb)
Rear brake hose
1. Install:
Copper washer 1
Brake hose 2
Copper washer 3
Union bolt 4
WARNING
Always use new copper washers.
CAUTION:
When installing the brake hose, first align
the tooth a on the copper washer 1 with
the projection b on the brake master cylin-
der. Then, align the pipe portion c on the
end of the brake hose with the tooth d on
the copper washer 1 and tighten the union
bolt.
T R..30 Nm (3.0 m · kg, 22 ft · lb)

5 - 26
CHASFRONT BRAKE AND REAR BRAKE
2. Install:
Brake hose holder 1
Screw (brake hose holder) 2
CAUTION:
After installing the brake hose holders,
make sure the brake hose does not contact
the spring (rear shock absorber). If it does,
correct its twist.
Brake fluid
1. Fill:
Brake fluid
Until the fluid level reaches “LOWER”
level line a.
WARNING
Use only the designated quality brake
fluid:
otherwise, the rubber seals may deterio-
rate, causing leakage and poor brake per-
formance.
Refill with the same type of brake fluid;
mixing fluids may result in a harmful chem-
ical reaction and lead to poor performance.
Be careful that water does not enter the
master cylinder when refilling. Water will
significantly lower the boiling point of the
fluid and may result in vapor lock.
CAUTION:
Brake fluid may erode painted surfaces or
plastic parts. Always clean up spilled fluid
immediately.
ÅFront
ıRear
Recommended brake fluid:
DOT #4
T R..1 Nm (0.1 m · kg, 0.7 ft · lb)
Å
ı

5 - 27
CHASFRONT BRAKE AND REAR BRAKE
2. Air bleed:
Brake system
Refer to “BRAKE SYSTEM AIR
BLEEDING” section in the CHAPTER
3.
3. Inspect:
Brake fluid level
Fluid at lower level → Fill up.
Refer to “BRAKE FLUID LEVEL
INSPECTION” section in the CHAP-
TER 3.
4. Install:
[Front]
Diaphragm
Brake master cylinder cap 1
Screw (brake master cylinder cap) 2
[Rear]
Diaphragm
Reservoir tank cap 1
Screw (reservoir tank cap) 2
Brake master cylinder guard
CAUTION:
After installation, while pulling the brake
lever in or pushing down on the brake
pedal, check whether there is any brake
fluid leaking where the union bolts are
installed respectively at the brake master
cylinder and brake caliper.
ÅFront
ıRear
5. Install: (rear brake only)
Protector 1
Bolt (protector) 2
Å
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
ı
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)

5 - 28
CHASFRONT FORK
EC550000
FRONT FORK
Extent of removal:1 Front fork removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalFRONT FORK REMOVAL
Hold the machine by placing the
suitable stand under the engine.
WARNING
Support the machine securely so there is no
danger of it falling over.
Front wheel Refer to “FRONT WHEEL AND REAR
WHEEL” section.
Front brake caliper Refer to “FRONT BRAKE AND REAR
BRAKE” section.
Headlight
Handlebar Refer to “HANDLEBAR” section.
1 Protector 1
2 Brake hose holder 2
3 Pinch bolt (upper bracket) 2 Only loosening.
4 Cap bolt 1Loosen when disassembling the front fork.
5 Pinch bolt (lower bracket) 2 Only loosening.
6 Front fork 1
1