2004 YAMAHA YZ250F brake

SPEC
2 - 15
MAINTENANCE SPECIFICATIONS
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Nipple (spoke)—72 3 0.3 2.2
Rear wheel sprocket M8 × 1.25 6 42 4.2 30
Rear brake disc cover M6 × 1.0 2 7 0.7 5.1
Rear brake caliper protector M6 × 1.0 2 7 0.7 5.1
Drive chain puller adjust bolt and locknut M8 × 1.25 2 16 1.6 11
Engine mounting:
Engine and engine bracket (front) M10 × 1.25 1 69 6.9 50
Engine and frame (lower) M10 × 1.25 1 69 6.9 50
Upper engine bracket and frame M8 × 1.25 2 44 4.4 32
Lower engine bracket and frame M8 × 1.25 4 34 3.4 24
Engine and engine bracket (upper) M10 × 1.25 1 55 5.5 40
Lower engine guard M6 × 1.0 3 10 1.0 7.2
Right engine guard M8 × 1.25 2 23 2.3 17
CDI unit bracket M6 × 1.0 1 10 1.0 7.2
Pivot shaft and nut M16 × 1.5 1 85 8.5 61
Relay arm and swingarm M14 × 1.5 1 80 8.0 58
Relay arm and connecting rod M14 × 1.5 1 80 8.0 58
Connecting rod and frame M14 × 1.5 1 80 8.0 58
Rear shock absorber and frame M10 × 1.25 1 56 5.6 40
Rear shock absorber and relay arm M10 × 1.25 1 53 5.3 38
Rear frame (upper) M8 × 1.25 1 32 3.2 23
Rear frame (lower) M8 × 1.25 2 29 2.9 21
Swingarm and brake hose holder M5 × 0.8 4 1 0.1 0.7
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
Upper drive chain tensioner M8 × 1.25 1 19 1.9 13
Lower drive chain tensioner M8 × 1.25 1 20 2.0 14
Drive chain support M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
Fuel tank M6 × 1.0 2 10 1.0 7.2
Fuel cock M6 × 1.0 2 7 0.7 5.1
Seat set bracket and fuel tank M6 × 1.0 1 7 0.7 5.1
Hooking screw (fitting band) and fuel tank M6 × 1.0 1 7 0.7 5.1
Fuel tank bracket and fuel tank M6 × 1.0 4 7 0.7 5.1
Air scoop and fuel tank M6 × 1.0 6 6 0.6 4.3
Air scoop and radiator guard (lower) M6 × 1.0 2 6 0.6 4.3
Front fender M6 × 1.0 4 7 0.7 5.1
Rear fender (front) M6 × 1.0 2 7 0.7 5.1
Rear fender (rear) M6 × 1.0 2 12 1.2 8.7
Side cover M6 × 1.0 2 7 0.7 5.1
Seat M8 × 1.25 2 23 2.3 17
Number plate M6 × 1.0 1 7 0.7 5.1

2 - 18
SPEC

CABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1
Fuel tank breather hose
2
Clutch cable
3
Oil tank breather hose
4
Hot starter cable
5
Cylinder head breather hose
6
Cable guide
7
Hose guide
8
Brake hose
9
Engine stop switch lead
0
Clamp
A
Sub-wire harness
B
Throttle position sensor lead
C
Neutral switch lead
D
Oil hose
E
CDI magneto lead
F
Radiator breather hose
G
Carburetor breather hose
H
Carburetor overflow hose
Å
Insert the end of the fuel tank
breather hose into the hole in
the steering stem cap.
ı
Pass the hot starter cable
between the cylinder head
breather hose, oil tank breather
hose and ignition coil, then on
the outside of the left engine
bracket.
Ç
Pass the clutch cable through
the cable guides.
Î
Pass the clutch cable in front of
the radiator mounting boss.
‰
Fit the brake hose into the
guides on the protector.
Ï
Fasten the neutral switch lead
and CDI magneto lead to the
cable guide with a plastic locking
tie and cut off the tie end.
Ì
Fasten the engine stop switch
lead, neutral switch lead and
CDI magneto lead.
Ó
Fasten the engine stop switch
lead and sub-wire harness at the
protecting tube for the engine
stop switch lead.
È
Fasten the sub-wire harness
and hot starter cable at the white
tape for the sub-wire harness.
Ô
Fasten the sub-wire harness.

Pass the sub-wire harness
between the engine brackets.
A
C-C
B
CC
A
D
F
C
1
2
3
4
5 6 6 78
G
H
G0
0DCB0 0 0
A 9
0
0
B
0 Ï
Ì
Ó
Ô

Ô
Ò
˜
ˆ Ø 0 E F
∏ Œ Å
ı
Ç Î Ç ‰
Â
0
È

2 - 21
SPECCABLE ROUTING DIAGRAM
1Brake master cylinder
2Brake hose holder
3Brake hoseÅInstall the brake hose so that its pipe portion
directs as shown and lightly touches the projection
on the brake caliper.
ıPass the brake hose into the brake hose holders.
ÇIf the brake hose contacts the spring (rear shock
absorber), correct its twist.
ÎInstall the brake hose so that its pipe portion
directs as shown and lightly touches the projection
on the brake master cylinder.

2 - 22
SPECCABLE ROUTING DIAGRAM
1Throttle cable
2Fuel tank breather hose
3Clamp
4Clutch cable
5Hot starter cable
6Engine stop switch lead
7Brake hose
8Hose guideÅFasten the engine stop switch lead to the handlebar.
ıPass the brake hose in front of the number plate.
3
6
12
3
4
5
6
7
8ı Å
A
A

3 - 2
INSP
ADJ

MAINTENANCE INTERVALS
SHIFT FORK, SHIFT CAM, GUIDE BAR
Inspect
●
Inspect wear
ROTOR NUT
Retighten
●

●

EXHAUST PIPE, SILENCER, PRO-
TECTOR
Inspect and retighten
Clean
Replace
●

●

●

●
* Whichever comes first
CRANK
Inspect and clean
●

●

CARBURETOR
Inspect, adjust and clean
●

●

SPARK PLUG
Inspect and clean
Replace
●

●

●

DRIVE CHAIN
Lubricate, slack, alignment
Replace
●

●

●
Use chain lube
Chain slack: 40 ~ 50 mm
(1.6 ~ 2.0 in)
COOLING SYSTEM
Check coolant level and leakage
Check radiator cap operation
Replace coolant
Inspect hoses
●

●

●

●

●
Every two years
OUTSIDE NUTS AND BOLTS
Retighten
●

●
Refer to “STARTING
AND BREAK-IN” section
in the CHAPTER 1.
AIR FILTER
Clean and lubricate
Replace
●

●

●
Use foam air-filter oil or
equivalent oil
OIL FILTER
Replace
●●
OIL STRAINER (frame)
Clean
●
FRAME
Clean and inspect
●

●

FUEL TANK, COCK
Clean and inspect
●

●

BRAKES
Adjust lever position and pedal height
Lubricate pivot point
Check brake disc surface
Check fluid level and leakage
Retighten brake disc bolts, caliper
bolts, master cylinder bolts and union
bolts
Replace pads
Replace brake fluid
●

●

●

●

●

●

●

●

●

●

●

●
Every one year
FRONT FORKS
Inspect and adjust
Replace oil
Replace oil seal
●

●

●

●

●
Suspension oil “01” ItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)
As re-
quiredRemarks
1
2
3

3 - 4
INSP
ADJ
PRE-OPERATION INSPECTION AND MAINTENANCE
EC320000
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating
condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator cap.
Check the cooling system for leakage.P.3-5 ~ 9
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-13
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-13 ~ 17
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-9
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-10
Brakes Check the play of front brake and effect of front and rear brake. P.3-24 ~ 30
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-31 ~ 33
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-41 ~ 42
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-42 ~ 43
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-33 ~ 40
Cables (wires)Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or
when the front forks travel up and down.—
Exhaust pipeCheck that the exhaust pipe is tightly mounted and has no
cracks.P.4-3 ~ 4
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-31
Lubrication Check for smooth operation. Lubricate if necessary. P.3-44
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-18
Lead connectorsCheck that the CDI magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-6
SettingsIs the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs
before racing? Are inspection and maintenance completely
done?P.7-1 ~ 22

3 - 24
INSP
ADJ

CHASSIS/BRAKE SYSTEM AIR BLEEDING
EC360000
CHASSIS
EC361012
BRAKE SYSTEM AIR BLEEDING
WARNING

Bleed the brake system if:

The system has been disassembled.

A brake hose has been loosened or
removed.

The brake fluid is very low.

The brake operation is faulty.
A dangerous loss of braking performance
may occur if the brake system is not prop-
erly bled.
1. Remove:

Brake master cylinder cap

Diaphragm

Reservoir float (front brake)

Protector (rear brake)
2. Bleed:

Brake fluid
Å
Front
ı
Rear
Air bleeding steps:
a. Add proper brake fluid to the reservoir.
b. Install the diaphragm. Be careful not to
spill any fluid or allow the reservoir to
overflow.
c. Connect the clear plastic tube
2
tightly
to the caliper bleed screw
1
.
d. Place the other end of the tube into a
container.
e. Slowly apply the brake lever or pedal
several times.
f. Pull the lever in or push down on the
pedal. Hold the lever or pedal in position.
g. Loosen the bleed screw and allow the
lever or pedal to travel towards its limit.
h. Tighten the bleed screw when the lever
or pedal limit has been reached; then
release the lever or pedal.
T R..

Bleed screw:
6 Nm (0.6 m • kg, 4.3 ft • lb)
i. Repeat steps (e) to (h) until of the air
bubbles have been removed from the
system.
Å
ı

3 - 25
INSP
ADJ

FRONT BRAKE ADJUSTMENT
3. Install:

Protector (rear brake)

Reservoir float (front brake)

Diaphragm

Brake master cylinder cap
NOTE:

If bleeding is difficult, it may be necessary to
let the brake fluid system stabilize for a few
hours. Repeat the bleeding procedure when
the tiny bubbles in the system have disap-
peared.
j. Add brake fluid to the level line on the
reservoir.
WARNING

Check the operation of the brake after
bleeding the brake system.
EC362040
FRONT BRAKE ADJUSTMENT
1. Check:

Brake lever position
a

2. Remove:

Brake lever cover
3. Adjust:

Brake lever position
4. Install:

Brake lever cover
Brake lever position
a
:
Standard position Extent of adjustment
95 mm (3.74 in)76 ~ 97 mm
(2.99 ~ 3.82 in)
Brake lever position adjustment steps:

Loosen the locknut
1
.

Turn the adjusting bolt
2
until the lever
position
a
is within specified position.

Tighten the locknut.
T R..

Locknut:
5 Nm (0.5 m • kg, 3.6 ft • lb)
CAUTION:
Be sure to tighten the locknut, as it will

cause poor brake performance.