2006 YAMAHA YZ250LC oil

1-14
STARTING AND BREAK-IN
GEN
INFO
EC194001
BREAK-IN PROCEDURES
1. Before starting the engine, fill the fuel tank
with a break-in oil-fuel mixture as follows.
2. Perform the pre-operation checks on the
machine.
3. Start and warm up the engine. Check the
idle speed, and check the operation of the
controls and the “ENGINE STOP” button.
4. Operate the machine in the lower gears at
moderate throttle openings for five to eight
minutes. Stop and check the spark plug con-
dition; it will show a rich condition during
break-in.
5. Allow the engine to cool. Restart the engine
and operate the machine as in the step
above for five minutes. Then, very briefly
shift to the higher gears and check full-throt-
tle response. Stop and check the spark
plug.
6. After again allowing the engine to cool,
restart and run the machine for five more
minutes. Full throttle and the higher gears
may be used, but sustained full-throttle
operation should be avoided. Check the
spark plug condition.
7. Allow the engine to cool, remove the top
end, and inspect the piston and cylinder.
Remove any high spots on the piston with
#600 grit wet sandpaper. Clean all compo-
nents and carefully reassemble the top end.
8. Drain the break-in oil-fuel mixture from the
fuel tank and refill with the specified mix.
9. Restart the engine and check the operation
of the machine throughout its entire operat-
ing range. Stop and check the spark plug
condition. Restart the machine and operate
it for about 10 to 15 more minutes. The
machine will now be ready to race.
Mixing oil: Mixing ratio:
Yamalube “2-R” 15:1
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1-18
CLEANING AND STORAGE
GEN
INFO
EC1B2001
STORAGE
If your machine is to be stored for 60 days or
more, some preventive measures must be taken
to avoid deterioration. After cleaning the
machine thoroughly, prepare it for storage as fol-
lows:
1. Drain the fuel tank, fuel lines, and the carbu-
retor float bowl.
2. Remove the spark plug, pour a tablespoon
of SAE 10W-30 motor oil in the spark plug
hole, and reinstall the plug. With the engine
stop switch pushed in, kick the engine over
several times to coat the cylinder walls with
oil.
3. Remove the drive chain, clean it thoroughly
with solvent, and lubricate it. Reinstall the
chain or store it in a plastic bag tied to the
frame.
4. Lubricate all control cables.
5. Block the frame up to raise the wheels off
the ground.
6. Tie a plastic bag over the exhaust pipe out-
let to prevent moisture from entering.
7. If the machine is to be stored in a humid or
salt-air environment, coat all exposed metal
surfaces with a film of light oil. Do not apply
oil to rubber parts or the seat cover.
NOTE:
Make any necessary repairs before the machine
is stored.
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2-1
GENERAL SPECIFICATIONSSPEC
Model name: YZ250V (USA, CDN)
YZ250 (EUROPE, ZA)
YZ250V (AUS, NZ)
Model code number: 1P85 (USA, CDN)
1P86 (EUROPE)
1P88 (AUS, NZ, ZA)
Dimensions:USA, AUS, NZ, ZACDN EUROPE
Overall length 2,178 mm 2,182 mm 2,184 mm
(85.7 in) (85.9 in) (86.0 in)
Overall width 827 mm←←
(32.6 in)
Overall height 1,305 mm 1,308 mm 1,309 mm
(51.4 in) (51.5 in) (51.5 in)
Seat height 994 mm 996 mm 997 mm
(39.1 in) (39.2 in) (39.3 in)
Wheelbase 1,481 mm←←
(58.3 in)
Minimum ground clearance 382 mm 384 mm 385 mm
(15.0 in) (15.1 in) (15.2 in)
Dry weight:
Without oil and fuel 96.0 kg (211.6 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 9.2~10.9 : 1 (For USA and CDN)
8.9~10.6 : 1 (For EUROPE, AUS, NZ and ZA)
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 Premium unleaded gasoline
only with a research octane
number of 95 or higher
Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal)
EC200000
SPECIFICATIONSEC211000
GENERAL SPECIFICATIONS
1P8-9-31-2 5/19/05 10:30 AM Page 2

2-2
GENERAL SPECIFICATIONSSPEC
Carburetor:
Type/Manufacturer PWK38S/KEIHIN
Spark plug:
Type/Manufacturer BR8EG/NGK (resistance type)
Gap 0.5~0.6 mm (0.020~0.024 in)
Clutch type: Wet, multiple-disc
Transmission:
Primary reduction system Gear
Primary reduction ratio 63/21 (3.000)
Secondary reduction system Chain drive
Secondary reduction ratio 50/14 (3.571)
Transmission type Constant mesh, 5-speed
Operation Left foot operation
Gear ratio: 1st 27/14 (1.929)
2nd 23/15 (1.533)
3rd 23/18 (1.278)
4th 24/22 (1.091)
5th 20/21 (0.952)
Chassis:USA, ZA, AUS, NZEUROPE CDN
Frame type Semi double ←←
cradle
Caster angle 26.9° 27.1° 26.9°
Trail115 mm (4.53 in) 118 mm (4.65 in) 116 mm (4.57 in)
T ire:
Type With tube
Size (front) 80/100-21 51M
Size (rear) 110/90-19 62M
T ire pressure (front and rear) 100 kPa (1.0 kgf/cm2, 15 psi)
Brake:
Front brake type Single disc brake
Operation Right hand operation
Rear brake type Single disc brake
Operation Right foot operation
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (link type monocross suspension)
Shock absorber:
Front shock absorber Coil spring/oil damper
Rear shock absorber Coil spring/Gas, oil damper
Wheel travel:
Front wheel travel 300 mm (11.8 in)
Rear wheel travel 315 mm (12.4 in)
Electrical:
Ignition system CDI magneto
2
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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 EUROPEAUS, NZ, ZA
Type/Manufacturer PWK38S/←←…
KEIHIN
I.D. mark 1P85 30 1P86 40 1P87 50…
Main jet (M.J.) #178 #180 #178…
Main air jet (M.A.J) #200←←…
Jet needle-clip position (J.N.) N3EJ-2 N3EW-3 N3EW-2…
Main nozzle (N.J.) ø2.9←←…
Cutaway (C.A.) #7←←…
Pilot jet (P.J.) #50 #52 #50…
Pilot air screw (P.A.S.) 1 2-1/4 1-1/4…
(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…
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2-5
MAINTENANCE SPECIFICATIONSSPEC
Part to be tightened Thread size Q’tyT ightening torqueNm m•kg ft•lb
Spark plug
M14S×1.25 1 20 2.0 14
Cylinder head (nut) M 8 ×1.25 6 25 2.5 18
(stud) M 8 ×1.25 6 13 1.3 9.4
Cylinder (nut) M10 ×1.25 4 42 4.2 30
(stud) M10 ×1.25 4 13 1.3 9.4
Power valve :
Holder M 5 ×0.8 2 6 0.6 4.3
Link rod M 5 ×0.8 2 6 0.6 4.3
Push rod M 5 ×0.8 1 5 0.5 3.6
Thrust plate M 5 ×0.8 1 6 0.6 4.3
Side holder M 5 ×0.8 4 4 0.4 2.9
Link lever M 4 ×0.7 1 4 0.4 2.9
Pulley M 4 ×0.7 2 4 0.4 2.9
Cover M 5 ×0.8 4 4 0.4 2.9
Governor fork M 4 ×0.7 2 5 0.5 3.6
Housing M 5 ×0.8 4 5 0.5 3.6
Impeller M 8 ×1.25 1 14 1.4 10
Water pump housing cover M 6 ×1.0 4 10 1.0 7.2
Coolant drain bolt M 6 ×1.0 1 10 1.0 7.2
Radiator M 6 ×1.0 6 10 1.0 7.2
Radiator panel M 6 ×1.0 2 10 1.0 7.2
Radiator hose clamp M 6 ×1.0 8 2 0.2 1.4
Air filter element M 6 ×1.0 1 2 0.2 1.4
Carburetor joint M 6 ×1.0 5 10 1.0 7.2
Air filter case M 6 ×1.0 4 8 0.8 5.8
Air filter guide clamp M 5 ×0.8 1 1 0.1 0.7
Reed valve M 3 ×0.5 4 1 0.1 0.7
Throttle cable adjust bolt and locknut M 8 ×1.25 1 7 0.7 5.1
Throttle cable M 6 ×0.75 1 4 0.4 2.9
Exhaust pipe (front) M 6 ×1.0 1 14 1.4 10
Exhaust pipe (rear) M 6 ×1.0 1 12 1.2 8.7
Exhaust pipe stay (front) M 8 ×1.25 1 25 2.5 18
Exhaust pipe stay (rear) M 6 ×1.0 1 12 1.2 8.7
Silencer:
Silencer and fram M 6 ×1.0 2 12 1.2 8.7
Fiber (For USA and CDN) M 6 ×1.0 2 10 1.0 7.2
Fiber (Except for USA and CDN) M 6 ×1.0 4 10 1.0 7.2
Crankcase M 6 ×1.0 11 14 1.4 10
Crankcase cover (left) M 6 ×1.0 5 5 0.5 3.6
Chain cover M 6 ×1.0 2 5 0.5 3.6
Crankcase cover (right) M 6 ×1.0 9 10 1.0 7.2
Bearing plate cover (drive axle left) M 6 ×1.0 2 10 1.0 7.2
Bearing plate cover (main axle right) M 6 ×1.0 2 10 1.0 7.2
Holder M 6 ×1.0 2 10 1.0 7.2
Oil drain bolt M12 ×1.5 1 23 2.3 17
Oil check bolt M 6 ×1.0 1 10 1.0 7.2


 
 
 
 
 
1P8-9-31-2 5/19/05 10:30 AM Page 6

2-7
MAINTENANCE SPECIFICATIONSSPEC
EC212201
CHASSIS
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing…
Front suspension: USA, CDN, ZA,
EUROPE
AUS, NZ
Front fork travel
300 mm (11.8 in)←…
Fork spring free length
454 mm (17.9 in)←449 mm (17.7 in)
Spring rate, STD K=4.2 N/mm←…
(0.428 kg/mm,
24.0 lb/in)
Optional spring Yes←…
Oil capacity 527 cm
3532 cm3…
(18.6 Imp oz, (18.7 Imp oz,
17.8 US oz) 18.0 US oz)
Oil grade Suspension oil ←…
“S1”
Inner tube outer diameter 48 mm (1.89 in)←…
Front fork top endZero mm (Zero in)←…
Rear suspension: USA, CDN, ZA,
EUROPE
AUS, NZ
Shock absorber travel
131.5 mm (5.18 in)←…
Spring free length
Approx. 265 mm←…
(10.43 in)
Fitting length
One I.D. paint mark One I.D. paint mark
255 mm (10.04 in) 252 mm (9.92 in)…
Two I.D. paint marks Two I.D. paint marks
261 mm (10.28 in) 258 mm (10.16 in)…
Three I.D. paint marks Three I.D. paint marks
252.5 mm (9.94 in)249.5 mm (9.82 in)…

One I.D. paint mark
245.5 ~ 263.5 mm←…
(9.67 ~ 10.37 in)
Two I.D. paint marks
251.5 ~ 269.5 mm←…
(9.90 ~ 10.61 in)
Three I.D. paint marks
243.0 ~ 261.0 mm←…
(9.57 ~ 10.28 in)
Spring rate, STDK=48.0 N/mm ←…
(4.90 kg/mm,
274.4 lb/in)
Optional spring Yes←…
Enclosed gas pressure 1,000 kPa ←…
(10 kg/cm
2,
142 psi)
Swingarm:
Swingarm free play limit
End…
1.0 mm (0.04 in)
Side clearance…
0.2~0.9 mm
(0.008~0.035 in)
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2-12
MAINTENANCE SPECIFICATIONSSPEC
EC212300
ELECTRICAL
Part to be tightened Thread size Q’tyT ightening torqueNm m•kg ft•lb
Stator M 6 ×1.0 3 7 0.7 5.1
Rotor M12 ×1.25 1 56 5.6 40
Ignition coil M 6 ×1.0 2 7 0.7 5.1
Neutral switch (Except for USA and CDN) M 5 ×0.8 2 4 0.4 2.9
Item Standard Limit
Ignition system:
Ignition timing (B.T.D.C.) 0.18 mm (0.007 in)…
Advancer type Electrical…
CDI:
Magneto-model (stator)/Manufacturer 5CU-20/YAMAHA…
Source coil 1 resistance (color) 720~1,080 Ωat 20°C (68°F)…
(Black-Black/Red)
Source coil 2 resistance (color) 44~66 Ωat 20°C (68°F)…
(Green/Blue-Green/White)
Pickup coil resistance (color) 248~372 Ωat 20°C (68°F)…
(White/Blue-White/Red)
CDI unit-model/Manufacturer 1P8-00/YAMAHA…
Ignition coil:
Model/Manufacturer 1P8-00/YAMAHA…
Minimum spark gap 6 mm (0.24 in)…
Primary winding resistance 0.20~0.30 Ωat 20°C (68°F)…
Secondary winding resistance 9.5~14.3 kΩat 20°C (68°F)…
Spark plug cap:
Resistance 4~6 kΩat 20°C (68°F)…
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