2003 YAMAHA YZ250LC brake fluid

2-8
MAINTENANCE SPECIFICATIONSSPEC
Item Standard Limit
Wheel:
Front wheel type Spoke wheel…
Rear wheel type Spoke wheel…
Front rim size/Material 21 ×1.60/Aluminum…
Rear rim size/Material 19 ×2.15/Aluminum…
Rim runout limit:
Radial…
2.0 mm (0.08 in)
Lateral…
2.0 mm (0.08 in)
Drive chain
Type/Manufacturer DID520DMA2 SDH/DAIDO…
Number of links 113 links + joint…
Chain slack 40~50 mm (1.6~2.0 in)…
Chain length (10 links)…
152.5 mm (6.004 in)
Front disc brake:
Disc outside dia. ×Thickness 250 ×3.0 mm 250 ×2.5 mm
(9.84 ×0.12 in) (9.84 ×0.10 in)
Pad thickness 4.4 mm (0.17 in) 1.0 mm (0.04 in)
Master cylinder inside dia. 11.0 mm (0.433 in)…
Caliper cylinder inside dia. 27.0 mm (1.063 in) ×2…
Brake fluid type DOT #4…
Rear disc brake:
Disc outside dia. ×Thickness 245 ×4.0 mm 245 ×3.5 mm
(9.65 ×0.16 in) (9.65 ×0.14 in)
Deflection limit…
0.15 mm (0.006 in)
Pad thickness 6.4 mm (0.25 in) 1.0 mm (0.04 in)
Master cylinder inside dia. 11.0 mm (0.433 in)…
Caliper cylinder insdie dia. 25.4 mm (1.000 in)…
Brake fluid type DOT #4…
Brake lever & brake pedal:
Brake lever position 95 mm (3.74 in)…
Brake pedal height Zero mm (Zero in)…
(vertical height above footrest top)
Clutch lever free play (lever end) 8~13 mm (0.31~0.51 in)…
Throttle grip free play 3~5 mm (0.12~0.20 in)…
5UP-9-30-2 5/24/02 5:18 PM Page 9

INSP
ADJ
3-2
MAINTENANCE INTERVALS
3
Item Remarks
COOLING SYSTEM
Check coolant level and leakage
Check radiator cap operation
Replace coolantEvery two years
Inspect hoses
OUTSIDE NUTS AND BOLTS Refer to “STARTING
RetightenAND BREAK-IN” section
in the CHAPTER 1.
AIR FILTER
Clean and lubricateUse foam air-filter oil or
Replaceequivalent oil
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 fluidEvery one year
FRONT FORKS
Inspect and adjust
Replace oilSuspension oil “01”
Replace oil seal
FRONT FORK OIL SEAL AND DUST SEAL
Clean and lubeLithium base grease
REAR SHOCK ABSORBER
(After
Inspect and adjustrain ride)
Lube Molybdenum disulfide grease
Retighten
CHAIN GUARD AND ROLLERS
Inspect
SWINGARM
Inspect, lube and retightenMolybdenum disulfide grease
RELAY ARM, CONNECTING ROD
Inspect, lube and retightenMolybdenum disulfide grease
STEERING HEAD
Inspect free play and retighten
Clean and lubeLithium base grease
Replace bearing
TIRE, WHEELS
Inspect air pressure, wheel run-out,

tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
LubricateLithium base grease
THROTTLE, CONTROL CABLE
Check routing and connectionYamaha cable lube or
LubricateSAE 10W-30 motor oil
After
break-
inEvery
raceEvery
thirdEvery
fifthAs re-
quired
5UP-9-30-3A 5/24/02 5:19 PM Page 3

3-17
CHASSIS/BRAKE SYSTEM AIR BLEEDING
INSP
ADJ
EC360000
CHASSIS
EC361012
BRAKE SYSTEM AIR BLEEDING
w
Bleed the brake system if:
9The system has been disassembled.
9A brake hose has been loosened or removed.
9The brake fluid is very low.
9The brake operation is faulty.
A dangerous loss of braking performance may
occur if the brake system is not properly
bleed.
1. Remove:
9Master cylinder cap
9Diaphragm
9Protector (rear brake)
2. Bleed:
9Brake fluid
ÅFront
ıRear
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
2tightly 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 ped-
al. 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 re-
lease the lever or pedal.
i. Repeat steps (e) to (h) until of the air
bubbles have been removed from the
system.
Bleed screw:
6 Nm (0.6 m•kg, 4.3 ft•lb)
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3-18
FRONT BRAKE ADJUSTMENT
INSP
ADJ
3. Install:
9Protector (rear brake)
9Diaphragm
9Master cylinder cap
EC362041
FRONT BRAKE ADJUSTMENT
1. Check:
9Brake lever position a
2. Remove:
9Lever cover
3. Adjust:
9Brake lever position
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
disappeared.
j. Add brake fluid to the level line on the
reservoir.
w
Check the operation of the brake after
bleeding the brake system.
Brake lever position a a
:
Standard position Extent of adjutment
95 mm (3.74 in)76 ~ 97 mm
(2.99 ~ 3.82 in)
Brake lever position adjustment steps:
9Loosen the locknut 1.
9Turn the adjusting bolt 2until the lever
position a is within specified position.
9Tighten the locknut.
cC
Be sure to tighten the locknut, as it will
cause poor brake performance.
Locknut:
5 Nm (0.5 m•kg, 3.6 ft•lb)
4. Install:
9Lever cover
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3-20
FRONT BRAKE PAD INSPECTION AND REPLACEMENT
INSP
ADJ
9Loosen the pad pin 2.
9Remove the brake hose holder 3and
caliper 4from the front fork.
9Remove the pad pin and brake pads 5.
9Connect the transparent hose 6to the
bleed screw 7and place the suitable con-
tainer under its end.
9Loosen the bleed screw and push the
caliper piston in.
cC
Do not reuse the drained brake fluid.
9Tighten the bleed screw.
9Install the brake pads 8and pad pin.
NOTE:
9Install the brake pads with their projections
ainto the caliper recesses b.
9Temporarily tighten the pad pin at this point.
9Install the brake hose holder 9and caliper
0and tighten the pad pin q.
NOTE:
Fit the brake hose holder cut cover the pro-
jection
don the front fork and clamp the
brake hose.
Bleed screw:
6 Nm (0.6 m•kg, 4.3 ft•b)
Bolt (caliper):
23 Nm (2.3 m•kg, 17 ft•lb)
Pad pin:
18 Nm (1.8 m•kg, 13 ft•lb)
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3-21
REAR BRAKE PAD INSPECTION AND REPLACEMENT
INSP
ADJ
3. Inspect:
9Brake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
4. Check:
9Brake lever operation
A softy or spongy feeling Bleed brake
system.
Refer to “BRAKE SYSTEM AIR BLEED-
ING” section.
EC366060
REAR BRAKE PAD INSPECTION AND
REPLACEMENT
1. Inspect:
9Brake pad thickness a
Out of specification Replace as a set.
2. Replace:
9Brake pad
9Install the pad pin plug w.
Pad pin plug:
3 Nm (0.3 m•kg, 2.2 ft•lb)
Brake pad thickness a a
:
Standard
6.4 mm (0.25 in)
1.0 mm (0.04 in)
Brake pad replacement steps:
9Remove the protector 1and pad pin plug
2.
9Loosen the pad pin 3.
9Remove the rear wheel 4and caliper 5.
Refer to “FRONT WHEEL AND REAR
WHEEL” section in the CHAPTER 5.
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3-22
REAR BRAKE PAD INSPECTION AND REPLACEMENT
INSP
ADJ
9Remove the pad pin 6and brake pads 7.
9Connect the transparent hose 8to the
bleed screw 9and place the suitable con-
tainer under its end.
9Loosen the bleed screw and push the
caliper piston in.
cC
Do not reuse the drained brake fluid.
9Tighten the bleed screw.
9Install the brake pads 0and pad pin q.
NOTE:
9Install the brake pads with their projections
ainto the caliper recesses b.
9Temporarily tighten the pad pin at this point.
9Install the caliper wand rear wheel e.
Refer to “FRONT WHEEL AND REAR
WHEEL” section in the CHAPTER 5.
9Tighten the pad pin r.
9Install the pad pin plug tand protector y.
Bleed screw:
6 Nm (0.6 m•kg, 4.3 ft•lb)
Pad pin:
18 Nm (1.8 m•kg, 13 ft•lb)
Pad pin plug:
3 Nm (0.3 m•kg, 2.2 ft•lb)
Bolt (protector):
7 Nm (0.7 m•kg, 5.1 ft•lb)
3. Inspect:
9Brake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
4. Check:
9Brake pedal operation
A softy or spongy feeling Bleed brake
system.
Refer to “BRAKE SYSTEM AIR BLEEDING”
section.
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3-23
REAR BRAKE PAD INSULATOR INSPECTION
BRAKE FLUID LEVEL INSPECTIONINSP
ADJ
EC36b000
REAR BRAKE PAD INSULATOR
INSPECTION
1. Remove:
9Brake pad
Refer to
“REAR BRAKE PAD INSPEC-
TION AND REPLACEMENT” section.
2. Inspect:
9Rear brake pad insulator 1
Damage Replace.
EC367001
BRAKE FLUID LEVEL INSPECTION
1. Place the master cylinder so that its top is in
a horizontal position.
2. Inspect:
9Brake fluid level
Fluid at lower level Fill up.
aLower level
ÅFront
ıRear
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9Use only designated quality brake fluid to
avoid poor brake performance.
9Refill with same type and brand of brake flu-
id; mixing fluids could result in poor brake
performance.
9Be sure that water or other contaminants do
not enter master cylinder when refilling.
9Clean up spilled fluid immediately to avoid
erosion of painted surfaces or plastic parts.
Recommended brake fluid:
DOT #4
5UP-9-30-3B 5/24/02 5:21 PM Page 14