2001 YAMAHA YZ250F warning

5 - 15
CHASFRONT BRAKE AND REAR BRAKE
Brake caliper piston seal kit
1. Remove:
lDust seal 1
lPiston seal 2
NOTE:
Remove the piston seals and dust seals by
pushing them with a finger.
ACHTUNG:CAUTION:
Never attempt to pry out piston seals and
dust seals.
WARNING
Replace the piston seals and dust seals
whenever a caliper is disassembled.
Front
õRear

õ
EC5A4000
INSPECTION
Brake master cylinder
1. Inspect:
lBrake master cylinder inner surface a
Wear/scratches ® Replace master cyl-
inder assembly.
Stains ® Clean.
WARNING
Use only new brake fluid.
Front
õRear
2. Inspect:
lDiaphragm 1
Crack/damage ® Replace.
Front
õRear
õ
õ

3. Inspect:
lBrake master cylinder piston 1
lBrake master cylinder cup 2
Wear/damage/score marks ® Replace
brake master cylinder kit.
Front
õRear
õ

5 - 16
CHAS
Brake caliper
1. Inspect:
lBrake caliper cylinder inner surface a
Wear/score marks ® Replace brake
caliper assembly.
Front
õRear
õ
2. Inspect:
lBrake caliper piston 1
Wear/score marks ® Replace brake
caliper piston assembly.
WARNING
Replace the piston seals and dust seals 2
whenever a caliper is disassembled.
EC534301
Brake hose
1. Inspect:
lBrake hose 1
Crack/damage ® Replace.
EC5A5000
ASSEMBLY AND INSTALLATION
WARNING
lAll internal parts should be cleaned in
new brake fluid only.
lInternal parts should be lubricated with
brake fluid when installed.
lReplace the piston seals and dust seals
whenever a caliper is disassembled.
Brake caliper piston
1. Clean:
lBrake caliper
lPiston seal
lDust seal
lBrake caliper piston
Clean them with brake fluid.
FRONT BRAKE AND REAR BRAKE

5 - 17
CHAS
2. Install:
lPiston seal 1
lDust seal 2
WARNING
Always use new piston seals and dust
seals.
NOTE:
Fit the piston seals and dust seals onto the slot
on brake caliper correctly.
Front
õRear

õ
3. Install:
lBrake caliper piston 1
NOTE:
Apply the brake fluid on the piston wall.
ACHTUNG:CAUTION:
lFor the front brake caliper, install the pis-
ton with its depressed side a facing the
brake caliper. For the rear brake caliper,
install the piston with its shallow
depressed side b facing the caliper.
lNever force to insert.
Front
õRear
Front brake caliper
1. Install:
lPad support 1
lBrake pad 2
lPad pin 3
NOTE:
lInstall the brake pads with their projections
a into the brake caliper recesses b.
lTemporarily tighten the pad pin at this point.

õ
FRONT BRAKE AND REAR BRAKE

5 - 18
CHASFRONT BRAKE AND REAR BRAKE
2. Install:
lCopper washer 1
lUnion bolt 2
WARNING
Always use new copper washers.
ACHTUNG:CAUTION:
Install the brake hose so that its pipe por-
tion a directs as show and lightly touches
the projection b on the brake caliper.
T R..30 Nm (3.0 m · kg, 22 ft · lb)
3. Install:
lBrake hose holder 1
lBrake caliper 2
lBolt (brake caliper) 3
NOTE:
Fit the brake hose holder cut a over the pro-
jection b on the front fork and clamp the brake
hose.
4. Tighten:
lPad pin 4
5. Install:
lPad pin plug 5
Rear brake caliper
1. Install:
lPad support 1
lBrake pad 2
lPad pin 3
NOTE:
lInstall the brake pads with their projections
a into the brake caliper recesses b.
lTemporarily tighten the pad pin at this point.
T R..23 Nm (2.3 m · kg, 17 ft · lb)
T R..18 Nm (1.8 m · kg, 13 ft · lb)
T R..3 Nm (0.3 m · kg, 2.2 ft · lb)

5 - 19
CHASFRONT BRAKE AND REAR BRAKE
2. Install:
lBrake disc cover 1
lBolt (brake disc cover) 2
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
3. Install:
lCopper washer 1
lBrake hose 2
lUnion bolt 3
WARNING
Always use new copper washers.
ACHTUNG:CAUTION:
Install the brake hose to the brake caliper
with the paint a on the pipe facing the
brake caliper and with the pipe contacting
the brake caliper projection b.
T R..30 Nm (3.0 m · kg, 22 ft · lb)
4. Install:
lBrake caliper 1
lRear wheel 2
Refer to “FRONT WHEEL AND REAR
WHEEL” section.
5. Tighten:
lPad pin 3
6. Install:
lPad pin plug 4
T R..18 Nm (1.8 m · kg, 13 ft · lb)
T R..3 Nm (0.3 m · kg, 2.2 ft · lb)

5 - 20
CHASFRONT BRAKE AND REAR BRAKE
Brake master cylinder kit
1. Clean:
lBrake master cylinder
lBrake master cylinder kit
Clean them with brake fluid.
2. Install:
lBrake master cylinder cup (primary) 1
lBrake 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.
Front
õRear
õ

3. Install:
lSpring 1
To brake master cylinder piston 2.
NOTE:
Install the spring at the smaller dia. side.
Front
õRear

5 - 24
CHASFRONT BRAKE AND REAR BRAKE
4. Install:
lCopper washer 1
lBrake hose 2
lUnion bolt 3
WARNING
Always use new copper washers.
ACHTUNG:CAUTION:
Install the brake hose so that its pipe por-
tion a directs as show and lightly touches
the projection b on the brake master cylin-
der.
T R..30 Nm (3.0 m · kg, 22 ft · lb)
Rear brake hose
1. Install:
lCopper washer 1
lBrake hose 2
lCopper washer 3
lUnion bolt 4
WARNING
Always use new copper washers.
ACHTUNG: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 - 25
CHASFRONT BRAKE AND REAR BRAKE
2. Install:
lBrake hose holder 1
lScrew (brake hose holder) 2
ACHTUNG: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:
lBrake fluid
Until the fluid level reaches “LOWER”
level line a.
WARNING
lUse only the designated quality brake
fluid:
otherwise, the rubber seals may deterio-
rate, causing leakage and poor brake per-
formance.
lRefill with the same type of brake fluid;
mixing fluids may result in a harmful chem-
ical reaction and lead to poor performance.
lBe 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.
ACHTUNG:CAUTION:
Brake fluid may erode painted surfaces or
plastic parts. Always clean up spilled fluid
immediately.
Front
õRear
Recommended brake fluid:
DOT #4
T R..4 Nm (0.4 m · kg, 2.9 ft · lb)

õ