2002 YAMAHA YZ250LC engine oil

2-1
GENERAL SPECIFICATIONSSPEC
Model name: YZ250LC (EUROPE)
YZ250P1 (USA)
YZ250(P) (CDN, AUS, NZ, ZA)
Model code number: 5NX1 (USA, CDN, ZA)
5NX2 (EUROPE)
5NX4 (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)
Basic weight:
With oil and full fuel tank 105.0 kg (231 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 9.1~10.6 : 1
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
2
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2-4
MAINTENANCE SPECIFICATIONSSPEC
Item Standard Limit
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 engine mixing oil…
Carburetor:USA, CDN, ZA,
EUROPE
AUS, NZ
Type/Manufacturer
PWK38S/KEIHIN←…
I.D. mark 5NX1 00 5NX2 10…
Main jet (M.J.) #178 #175…
Main air jet (M.A.J) #200←…
Jet needle-clip position (J.N.) N3EJ-2 N3CW-3…
Main nozzle (N.J.) ø2.9←…
Cutaway (C.A.) #7←…
Pilot jet (P.J.) #50 #52…
Pilot air screw (P.A.S.) 1 1-3/8…
(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…
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2-13
CABLE ROUTING DIAGRAMSPEC
EC240000
CABLE ROUTING DIAGRAM
1Fuel tank breather hose
2Cable guide
3Throttle cable
4Clamp
5Clutch cable
6Wireharness
7“ENGINE STOP” button lead
8CDI unit
9CDI unit stay
0CDI unit band
qTPS (throttle position sensor)
lead
wSolenoid valve lead
eAir vent hose (left)
rTransmission oil breather hose
tOverflow hose
yAir vent hose (right)APass the fuel tank breather hose
between the handlebar and ten-
sion bar, then insert its end into
the hole of the number plate.
BPass the throttle cable and
“ENGINE STOP” button lead into
the cable guide. Align with the
cable guide the front end of the
tape on the throttle cable.
CPass the throttle cable and
“ENGINE STOP” button lead
over the radiator hose.
DClamp the throttle cable and
“ENGINE STOP” button lead with
the clamp ends downward.
EPass the clutch cable a little for-
ward of the extreme left nut that
holds the cylinder head.
FPass the wireharness between
the engine brackets.GPass the air vent hoses, overflow
hose and transmission oil
breather hose between the frame
and connecting rod.
HFit the CDI unit band into the CDI
unit stay till it stops.
IInsert the CDI unit into the CDI
unit band till it stops.
JClamp the TPS (throttle position
sensor) lead and solenoid valve
lead at the side of the TPS with
the clamp ends backward.
KClamp the air vent hoses.
LPass the air vent hoses, overflow
hose and transmission oil
breather hose so that all these
hoses do not contact the rear
shock absorber.
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2-14
CABLE ROUTING DIAGRAMSPEC
1Ground lead
2Ignition coil lead
3Clamp
4Wireharness
5CDI magneto lead
6YPVS breather hose
7Radiator breather hose
8Cable guide
9“ENGINE STOP” button lead
0Brake hose
APass the “ENGINE STOP” but-
ton lead on the inside of the
ignition coil lead and ground
lead.BClamp the “ENGINE STOP” but-
ton lead, ground lead, ignition
coil lead, wireharness and CDI
magneto lead with the clamp
ends downward.
In so doing, clamp the “ENGINE
STOP” button lead at its coupler
and do not allow the CDI mag-
neto lead to slacken.
CPass the radiator breather hose
outside the engine bracket and
inside the down-tube.Pass the
radiator breather hose inside
the CDI magneto lead.
DClamp the CDI magneto lead,
radiator breather hose and
YPVS breather hose. In so
doing, clamp the CDI magneto
lead at the rear of the down-
tube with the clamp ends for-
ward.EClamp the radiator breather
hose and CDI magneto lead at
the rear of the down-tube with
the clamp ends outward.
FPass the radiator breather hose
and CDI magneto lead in front
of the radiator hose.
GPass the radiator breather hose
between the frame and radiator.
HAlign the top of the brake hose
neck with the brake hose holder
bottom.
IPass the brake hose in front of
the axle boss,then fit it into the
hose groove so that the brake
hose does not contact the nut
(wheel axle).
JFit the brake hose into the guide
on the protector.
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2-15
CABLE ROUTING DIAGRAMSPEC
1Clutch cable
2Cable guide
3Ground lead
4Clamp
5Wireharness
6High tension cord
7Ignition coil
8Radiator breather hose
9“ENGINE STOP” button lead
0Throttle cable
qEngine bracketAPass the clutch cable into the
cable guide.
BClamp the clutch cable, high
tension cord and wireharness at
the protector of the high tension
cord so that the clamp passes
with its ends downward, as
shown.
CPosition the CDI magneto lead
coupler between the radiators.
DClamp the wireharness to the
right engine bracket.
EClamp the high tension cord,
throttle cable and wireharness
with the clamp ends downward,
so that the high tension cord
does not contact the engine
bracket installation nuts.FFasten the ground lead together
with the front installation portion
of the ingnition coil.
GPass the radiator breather hose
at the rear of the radiator hose.
HPosition the throttle cable,
“ENGINE STOP” button lead
and clutch cable as shown.
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3-4
PRE-OPERATION INSPECTION AND MAINTENANCE
INSP
ADJ
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.
EC321000
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
Coolant Check that coolant is filled up to the radiator filler cap.
Check the cooling system for leakage.P3-5~9
Fuel Check that a fresh mixture of oil and gasoline is filled in
the fuel tank. Check the fuel line for leakage.P1-12
Transmission oil Check that the oil level is correct. Check the crankcase
for leakage.P3-12~14
Gear shifter and clutch Check that gears can be shifted correctly in order and
that the clutch operates smoothly.P3-9
Throttle grip/Housing Check that the throttle grip operation and free play
are correctly adjusted. Lubricate the throttle grip and P3-10~11
housing, if necessary.
Brakes Check the play of front brake and effect of front and
rear brake.P3-17~23
Chain Check chain slack and alignment. Check that the chain
is lubricated properly.P3-24~26
Wheels Check for excessive wear and tire pressure. Check for
loose spokes and have no excessive play.P3-34~35
Steering Check that the handlebar can be turned smoothly and
have no excessive play.P3-35~36
Front forks and Check that they operate smoothly and there is no oil
rear shock absorber leakage.P3-26~33
Cables (wires) Check that the clutch and throttle cables move smooth-
ly. Check that they are not caught when the handlebars —
are turned or when the front forks travel up and down.
Muffler Check that the muffler is tightly mounted and has no
cracks.P3-15~16
Sprocket Check that the driven sprocket tightening bolt is
not loose.P3-24
Lubrication Check for smooth operation. Lubricate if necessary. P3-37
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P1-16
Lead connectors Check that the CDI magneto, CDI unit, and ignition coil
are connected tightly.P1-6
Settings Is the machine set suitably for the condition of the
racing course and weather or by taking into account the
P7-1~24
results of test runs before racing? Are inspection and
maintenance completely done?
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INSP
ADJ
3-7
RADIATOR CAP INSPECTION
cC
9
Do not mix more than one type of ethyl-
ene glycol antifreeze containing corro-
sion inhibitors for aluminum engine.
9Do not use water containing impurities
or oil.
7. Install:
9Radiator cap
Start the engine and warm it up for a sev-
eral minutes.
8. Check:
9Coolant level
Coolant level lowAdd coolant.
EC355000
RADIATOR CAP INSPECTION
1. Inspect:
9Seal (radiator cap) 1
9Valve and valve seat 2
Crack/DamageReplace.
Exist fur deposits 3Clean or replace.
Handling notes of coolant:
The coolant is harmful so it should be handled
with special care.
w
9
When coolant splashes to your eye.
Thoroughly wash your eye with water
and see your doctor.
9When coolant splashes to your clothes.
Quickly wash it away with water and then
with soap.
9When coolant is swallowed.
Quickly make him vomit and take him to
a doctor.
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INSP
ADJ
3-12
TRANSMISSION OIL LEVEL CHECK
3. Inspect:
9Air filter element
DamageReplace.
4. Apply:
9Foam-air-filter oil or engine mixing oil
To the element.
NOTE:
Squeeze out the excess oil. Element should be
wet but not dripping.
5. Install:
9Filter guide 1
NOTE:
Align the projection aon filter guide with the
hole bin air filter element.
6. Apply:
9Lithium soap base grease
On the matching surface aon air filter ele-
ment.
7. Install:
9Air filter element 1
9Washer
9Fitting bolt
NOTE:
Align the projection aon filter guide with the
hole bin air filter case.
EC35H002
TRANSMISSION OIL LEVEL CHECK
1. Start the engine, warm it up for several min-
utes and wait for five minutes.
2. Place the machine on a level place and hold
it up on upright position by placing the suit-
able stand under the engine.
2 Nm (0.2 m•kg, 1.4 ft•lb)
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