height YAMAHA YZ250LC 2004 Owners Manual

2-1
GENERAL SPECIFICATIONSSPEC
Model name: YZ250LC (EUROPE)
YZ250S (USA)
YZ250(S) (CDN, AUS, NZ, ZA)
Model code number: 5XF1 (USA, CDN, ZA)
5XF2 (EUROPE)
5XF4 (AUS, NZ)
Dimensions:USA, ZAAUS, NZ EUROPE CDN
Overall length 2,183 mm←2,182 mm←
(85.9 in) (85.9 in)
Overall width 827 mm←←←
(32.6 in)
Overall height 1,309 mm 1,296 mm 1,302 mm 1,307 mm
(51.5 in) (51.0 in) (51.3 in) (51.5 in)
Seat height 991 mm←990 mm←
(39.0 in) (39.0 in)
Wheelbase 1,481 mm←1,485 mm←
(58.3 in) (58.5 in)
Minimum ground clearance 395 mm←393 mm←
(15.6 in) (15.5 in)
Dry weight:
Without oil and fuel 97.0 kg (213.8 lb)
Engine:
Engine type Liquid cooled 2-stroke, gasoline
Cylinder arrangement Single cylinder, forward inclined
Displacement 249 cm
3(8.76 lmp oz, 8.42 US oz)
Bore ×Stroke 66.4 ×72 mm (2.614 ×2.835 in)
Compression ratio 9.1~10.9 : 1 (Expect for EUROPE)
9.0~10.6 : 1 (For EUROPE)
Starting system Kick starter
Lubrication system: Premix (30 : 1)(Yamalube 2-R)
Oil type or grade (2-Cycle):
Transmission oil Yamalube 4 (10W-30) or SAE 10W-30 type SE
motor oil
Periodic oil change 0.75 L (0.66 Imp qt, 0.79 US qt)
Total amount 0.80 L (0.70 Imp qt, 0.85 US qt)
Coolant capacity (including all routes): 1.20 L (1.06 Imp qt, 1.27 US qt)
Air filter: Wet type element
Fuel:
Type Except for ZA: Premium unleaded gasoline
only with a research octane
number of 95 or higher
For ZA: Premium gasoline
Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal)
EC200000
SPECIFICATIONSEC211000
GENERAL SPECIFICATIONS
5XF-9-30-2 5/15/03 3:54 PM Page 2

2-4
MAINTENANCE SPECIFICATIONSSPEC
Item Standard Limit
Clutch housing thrust clearance 0.17~0.23 mm (0.007~0.009 in) …
Clutch housing radial clearance 0.030~0.055 mm (0.001~0.002 in) …
Clutch release method Inner push, cam push …
Transmission:
Main axle deflection limit…
0.01 mm (0.0004 in)
Drive axle deflection limit…
0.01 mm (0.0004 in)
Shifter:
Shifting type Cam drum and guide bar…
Guide bar bending limit…
0.05 mm (0.0020 in)
Kick starter type: Kick and ratchet type…
Air filter oil grade (oiled filter):Foam-air-filter oil or equivalent oil…
Carburetor:USA, CDN, ZA,
EUROPE
AUS, NZ
Type/Manufacturer
PWK38S/KEIHIN←…
I.D. mark 5NX1 00 5UP2 10…
Main jet (M.J.) #178 #180…
Main air jet (M.A.J) #200←…
Jet needle-clip position (J.N.) N3EJ-2 N3EW-3…
Main nozzle (N.J.) ø2.9←…
Cutaway (C.A.) #7←…
Pilot jet (P.J.) #50 #52…
Pilot air screw (P.A.S.) 1 7/8…
(for reference only)
Valve seat size (V.S.)
ø3.8 mm (0.15 in)←…
Starter jet (G.S.) #85←…
Power jet (P.W.J.) #50←…
Float arm height (F.H.) 5.5~7.5 mm←…
(0.22~030 in)
Reed valve:
Thickness* 0.42 mm (0.017 in)…
Valve stopper height 10.3~10.7 mm (0.406~0.421 in)…
Valve bending limit…
0.2 mm (0.008 in)
Cooling:
Radiator core size:
Width 107.8 mm (4.24 in)…
Height 240 mm (9.45 in)…
Thickness 32 mm (1.26 in)…
Radiator cap opening pressure 95~125 kPa…
(0.95~1.25 kg/cm
2, 13.5~17.8 psi)
Radiator capacity (total) 0.63 L (0.55 Imp qt, 0.67 US qt)…
Water pump:
Type Single-suction centrifugal pump…
5XF-9-30-2 5/15/03 3:54 PM Page 5

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)…
5XF-9-30-2 5/15/03 3:54 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
5XF-9-30-3A 4/21/03 2:09 PM Page 3

3-19
REAR BRAKE ADJUSTMENT/
FRONT BRAKE PAD INSPECTION AND REPLACEMENTINSP
ADJ
EC365080
FRONT BRAKE PAD INSPECTION AND
REPLACEMENT
1. Inspect:
9Brake pad thickness a
Out of specification Replace as a set.
2. Replace:
9Brake pad
Brake pad thickness a a
:
Standard
4.4 mm (0.17 in)
1.0 mm (0.04 in)
Brake pad replacement steps:
9Remove the pad pin plug 1.
EC364005
REAR BRAKE ADJUSTMENT
1. Check:
9Brake pedal height a
Out of specificationAdjust.
NOTE:
The brake pedal height is the vertical distance
from the inside top end of the footrest.
2. Adjust:
9Brake pedal height
Brake pedal height a a
:
Zero mm (Zero in)
Pedal height adjustment steps:
9Loosen the locknut 1.
9Turn the adjusting nut 2until the pedal
height ais within specified height.
9Tighten the locknut.
w
9Adjust the pedal height between the
maximum Å Å
and the minimum ı ı
as
shown. (In this adjustment, the bolt 3 3
end b b
should protrude out of the thread-
ed portion 4 4
but not be less than 2 mm
(0.08 in) c c
away from the brake pedal
5 5
).
9After the pedal height adjustment, make
sure that the rear brake does not drag.
5XF-9-30-3B 5/6/03 6:31 PM Page 2

4-11
ENGCARBURETOR AND REED VALVE
EC464401
Jet needle
1. Inspect:
9Jet needle 1
Bends/Wear Replace.
9Clip groove
Free play exists/Wear Replace.
9Clip position
*For EUROPE
EC464511
Float height
1. Measure:
9Float height a
Out of specification Adjust.
Standard clip position:
No.2 Groove
*No.3 Groove
Float height:
5.5~7.5 mm (0.22~0.30 in)
Measurement and adjustment steps:
9Hold the carburetor in an upside down posi-
tion.
9Measure the distance between the mating
surface of the float chamber and top of the
float using a vernier calipers.
NOTE:
The float arm should be resting on the nee-
dle valve, but not compressing the needle
valve.
9If the float height is not within specification,
inspect the valve seat and needle valve.
9If either is worn, replace them both.
9If both are fine, adjust the float height by
bending the float tab bon the float.
9Recheck the float height.
5XF-9-30-4A 5/7/03 1:35 PM Page 22

4-12
ENGCARBURETOR AND REED VALVE
EC465000
ASSEMBLY AND INSTALLATION
EC465173
Reed valve
1. Install:
9Reed valve 1
9Stopper (reed valve) 2
9Screw (reed valve) 3
NOTE:
9Install the reed valve with the reed valve bend-
ing as shown.
9Note the cut ain the lower corner of the reed
and stopper plate.
cC
Tighten each screw gradually to avoid
warping.
1 Nm (0.1 m•kg, 0.7 ft•lb)
9Valve stopper height b
Out of specification  Adjust stopper/
Replace valve stopper.
Valve stopper height:
10.3 ~10.7 mm (0.406~0.421 in)
EC464600
Float
1. Inspect:
9Float 1
Damage Replace.
EC464701
Reed valve
1. Measure:
9Reed valve bending a
Out of specification Replace.
Reed valve bending limit:
0.2 mm (0.008 in)
5XF-9-30-4A 5/7/03 1:35 PM Page 24

3. Install:
9Spring 1
9Brake pedal 2
9O-ring 3
9Bolt (brake pedal) 4
9Clip 5
NOTE:
9Apply the lithium soap base grease on the
bolt, O-ring and brake pedal bracket.
9Install the clip with its stopper portion afac-
ing inward.
5-22
CHASFRONT BRAKE AND REAR BRAKE
26 Nm (2.6 m•kg, 19 ft•lb)
EC5A5911
Front brake hose
1. Install:
9Brake hose 1
To brake hose holder 2.
NOTE:
Before tightening the bolt (brake hose holder),
align the top aof the brake hose neck with the
brake hose holder bottom b. Then pass the
brake hose in front of the axle boss cand fit it
into the hose groove dso that the brake hose
does not contact the nut (wheel axle).
2. Install:
9Hose cover 1
9Plain washer 2
9Bolt [hose cover (M8)] 3
9Bolt [hose cover (M6)] 4
10 Nm (1.0 m•kg, 7.2 ft•lb)
16 Nm (1.6 m•kg, 11 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.
5XF-9-30-5A 4/21/03 9:58 PM Page 44