2005 YAMAHA YZ250LC brake

5-15
CHASFRONT BRAKE AND REAR BRAKE
EC533402
Piston seal kit
1. Remove:
9Dust seal 1
9Piston seal 2
NOTE:
Remove the piston seals and dust seals by
pushing them with a finger.
cC
Never attempt to pry out piston seals and
dust seals.
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Replace the piston seals and dust seals
whenever a caliper is disassembled.
AFront
BRear
EC5A4000
INSPECTION
EC534120
Master cylinder
1. Inspect:
9Master cylinder inner surface a
Wear/ScratchesReplace master cylinder
assembly.
StainsClean.
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Use only new brake fluid.
AFront
BRear
2. Inspect:
9Diaphragm 1
Crack/DamageReplace.
AFront
BRear
3. Inspect: (front brake only)
9Reservoir float 1
DamageReplace.
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5-16
CHASFRONT BRAKE AND REAR BRAKE
4. Inspect:
9Master cylinder piston 1
9Master cylinder cup 2
Wear/Damage/Score marksReplace master
cylinder kit.
AFront
BRear
EC534214
Caliper
1. Inspect:
9Caliper cylinder inner surface a
Wear/Score marksReplace caliper as-
sembly.
AFront
BRear
2. Inspect:
9Caliper piston 1
Wear/Score marksReplace caliper piston
assembly.
w
Replace the piston seals and dust seals 2 2
whenever a caliper is disassembled.
EC534301
Brake hose
1. Inspect:
9Brake hose 1
Crack/DamageReplace.
EC5A5000
ASSEMBLY AND INSTALLATION
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9All internal parts should be cleaned in
new brake fluid only.
9Internal parts should be lubricated with
brake fluid when installed.
9Replace the piston seals and dust seals
whenever a caliper is disassembled.
1P8-9-30-5A 19/5/04 9:28 AM Page 32

5-17
CHASFRONT BRAKE AND REAR BRAKE
EC5A5801
Caliper piston
1. Clean:
9Caliper
9Piston seal
9Dust seal
9Caliper piston
Clean them with brake fluid.
2. Install:
9Piston seal 1
9Dust seal 2
w
Always use new piston seals and dust
seals.
NOTE:
Fit the piston seals and dust seals onto the slot
on caliper correctly.
AFront
BRear
3. Install:
9Caliper piston 1
NOTE:
Apply the brake fluid on the piston wall.
cC
9Install the piston with its shallow
depressed side a a
facing the caliper.
9Never force to insert.
AFront
BRear
EC5A5700
Front caliper
1. Install:
9Pad support 1
9Brake pad 2
9Pad pin 3
NOTE:
9Install the brake pads with their projections
ainto the caliper recesses b.
9Temporarily tighten the pad pin at this point.
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5-18
CHASFRONT BRAKE AND REAR BRAKE
EC5A5121
Rear caliper
1. Install:
9Pad support 1
9Brake pad 2
9Pad pin 3
NOTE:
9Install the brake pads with their projections
ainto the caliper recesses b.
9Temporarily tighten the pad pin at this point.
2. Install:
9Disc cover 1
9Bolt (disc cover) 2 2. Install:
9Caliper 1
9Bolt (caliper) 2
3. Tighten:
9Pad pin 3
4. Install:
9Pad pin plug 4
23 Nm (2.3 m•kg, 17 ft•lb)
18 Nm (1.8 m•kg, 13 ft•lb)
3 Nm (0.3 m•kg, 2.2 ft•lb)
7 Nm (0.7 m•kg, 5.1 ft•lb)
18 Nm (1.8 m•kg, 13 ft•lb)
3 Nm (0.3 m•kg, 2.2 ft•lb)
3. Install:
9Caliper 1
9Rear wheel 2
Refer to “FRONT WHEEL AND REAR
WHEEL” section.
4. Tighten:
9Pad pin 3
5. Install:
9Pad pin plug 4
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5-19
CHASFRONT BRAKE AND REAR BRAKE
EC5A5220
Master cylinder kit
1. Clean:
9Master cylinder
9Master cylinder kit
Clean them with brake fluid.
2. Install:
9Master cylinder cup (primary) 1
9Master cylinder cup (secondary) 2
To master cylinder piston 3.
NOTE:
Apply the brake fluid on the master cylinder cup.
w
After installing, cylinder cup should be in-
stalled as shown direction. Wrong installa-
tion cause improper brake performance.
AFront
BRear
3. Install:
9Spring 1
To master cylinder piston 2.
NOTE:
Install the spring at the smaller dia. side.
AFront
BRear
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5-20
CHASFRONT BRAKE AND REAR BRAKE
4. Install:
[Front]
9Master cylinder kit 1
9Plain washer 2
9Circlip 3
9Master cylinder boot 4
To master cylinder 5.
[Rear]
9Master cylinder kit 1
9Push rod 2
9Circlip 3
9Master cylinder boot 4
To master cylinder 5.
NOTE:
9Apply the brake fluid on the master cylinder
kit.
9Apply the lithium soap base grease on the tip
of the push rod.
9When installing the circlip, use a long nose
circlip pliers.
AFront
BRear
EC5A5310
Front master cylinder
1. Install:
9Master cylinder 1
9Master cylinder bracket 2
9Bolt (master cylinder bracket) 3
NOTE:
9Install the bracket so that the arrow mark a
face upward.
9First tighten the bolts on the upper side of the
master cylinder bracket, and then tighten the
bolts on the lower side.
9 Nm (0.9 m•kg, 6.5 ft•lb)
2. Install:
9Brake lever 1
9Bolt (brake lever) 2
9Nut (brake lever) 3
NOTE:
Apply the lithium soap base grease on the
brake lever sliding surface, bolt and contacting
surface of the master cylinder piston.
6 Nm (0.6 m•kg, 4.3 ft•lb)
6 Nm (0.6 m•kg, 4.3 ft•lb)
1P8-9-30-5A 19/5/04 9:28 AM Page 40

5-21
CHASFRONT BRAKE AND REAR BRAKE
EC5A5401
Rear master cylinder
1. Install:
9Copper washer 1
9Brake hose 2
9Union bolt 3
w
Always use new copper washers.
cC
Install the brake hose so that its pipe por-
tion
a adirects as shown and lightly touch-
es the projection
b bon the master cylinder.
30 Nm (3.0 m•kg, 22 ft•lb)
2. Install:
9Master cylinder 1
9Bolt (master cylinder) 2
10 Nm (1.0 m•kg, 7.2 ft•lb)
3. Install:
9Spring 1
9Brake pedal 2
9O-ring 3
9Bolt (brake pedal) 4
9Clip 5
NOTE:
Apply the lithium soap base grease on the
bolt, O-ring and brake pedal bracket.
26 Nm (2.6 m•kg, 19 ft•lb)
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5-22
CHASFRONT BRAKE AND REAR BRAKE
2. Install:
9Brake hose holder 1
9Bolt (brake hose holder) 2
3. Install:
9Brake hose holder 1
9Nut (brake hose holder) 2
NOTE:
Align the top aof the brake hose holder with
the paint bof the brake hose.
10 Nm (1.0 m•kg, 7.2 ft•lb)
7 Nm (0.7 m•kg, 5.1 ft•lb)
4. Install:
9Pin 1
9Plain washer 2
9Cotter pin 3
NOTE:
After installing, check the brake pedal height.
Refer to “REAR BRAKE ADJUSTMENT” section
in the CHAPTER 3.
EC5A5911
Front brake hose
1. Install:
9Copper washer 1
9Brake hose 2
9Union bolt 3
w
Always use new copper washers.
cC
Install the brake hose so that its pipe por-
tion a a
directs as shown and lightly touch-
es the projection b b
on the caliper.
30 Nm (3.0 m•kg, 22 ft•lb)
1P8-9-30-5A 19/5/04 9:28 AM Page 44