ignition YAMAHA YZ250LC 2006 Manuale duso (in Italian)

CHAPTER 6
ELECTRICAL
ELECTRICAL COMPONENTS AND
WIRING DIAGRAM.....................................6-1
IGNITION SYSTEM.....................................6-2
SOLENOID VALVE SYSTEM......................6-7
TPS (THROTTLE POSITION SENSOR)
SYSTEM......................................................6-9
CHAPTER 7
TUNING
ENGINE.......................................................7-1
CHASSIS...................................................7-13
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1-7
SPECIAL TOOLS
GEN
INFO
EC140002
SPECIAL TOOLS
The proper special tools are necessary for complete and accurate tune-up and assembly. Using the
correct special tool will help prevent damage caused by the use of improper tools or improvised tech-
niques. The shape and part number used for the special tool differ by country, so two types are provid-
ed. Refer to the list provided to avoid errors when placing an order.
NOTE:
9For U.S.A. and Canada, use part number starting with “YM-”, “YU-” or “ACC -”.
9For others, use part number starting with “90890-”.
Part number Tool name / How to use IIIustration
YU-1135-A, 90890-01135Crankcase separating toolYU-1135-A 90890-01135
This tool is used to split the crankcase as well
as remove the crankshaft from either case.
YM-1189, 90890-01189 Flywheel puller
YM-1189 90890-01189
This tool is used to remove the flywheel magneto.
YU-1235, 90890-01235 Rotor holding tool
YU-1235 90890-01235
This tool is used when loosening or tightening the
flywheel magneto securing nut.
YU-3097, 90890-01252 Dial gauge and stand
YU-3097 90890-01252
YU-1256 Spark plug hole dial standYU-1256
These tools are used to set the ignition timing.
Crankcase installing tool
YU-90050 90890-01274
YU-90050, 90890-01274 PotYU-90063 90890-01275
YU-90050, 90890-01275 Bolt
90890-01278
YU-90063, 90890-01278 Adapter
These tools are used to install the crankshaft.
YU-1304, 90890-01304 Piston pin puller
YU-1304 90890-01304
This tool is used to remove the piston pin.
YU-24460-01,90890-01325Radiator cap testerYU-24460-01 90890-01325
YU-33984, 90890-01352 AdapterYU-33984 90890-01352
These tools are used for checking the cooling
system.
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1-8
SPECIAL TOOLS
GEN
INFO
Part number Tool name / How to use IIIustration
YU-33975, 90890-01403 Ring nut wrenchYU-33975 90890-01403
This tool is used when tighten the steering ring nut
to specification.
YM-01500, 90890-01500 Cap bolt wrench
YM-01500 90890-01500
This tool is used to loosen or tighten the base valve.
YM-01501, 90890-01501 Cap bolt ring wrench
YM-01501 90890-01501
This tool is used to loosen or tighten the damper
assembly.
YM-A0948, 90890-01502 Fork seal driver
YM-A0948 90890-01502
This tool is used when install the fork oil seal.
YU-3112-C, 90890-03112 Yamaha pocket tester
YU-3112-C 90890-03112
Use this tool to inspect the coil resistance,
output voltage and amperage.
YU-8036-B Inductive tachometer
YU-8036-B 90890-03113
90890-03113 Engine tachometer
This tool is needed for observing engine rpm.
YM-91042, 90890-04086 Clutch holding tool
YM-91042 90890-04086
This tool is used to hold the clutch when removing
or installing the clutch boss securing nut.
YM-34487 Dynamic spark tester
YM-34487 90890-06754
90890-06754 Ignition checker
This instrument is necessary for checking the igni-
tion system components.
ACC-QUICK-GS-KT Quick gasket
®ACC-QUICK-GS-KT 90890-85505
90890-85505 YAMAHA Bond No. 1215
This sealant (Bond) is used for crankcase mating
surface, etc.
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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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2-12
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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2-15
CABLE ROUTING DIAGRAMSPEC
1Ignition coil lead
2Clamp
3CDI magneto lead
4Neutral switch lead (except for
USA and CDN)
5Radiator breather hose
6Connector cover
AClamp the ignition coil lead to
the frame at its locating tape.
Clamp it in front of the radiator
fitting boss.BClamp the CDI magneto lead to
the frame at its locating tape.
Clamp it at the rear of the radia-
tor fitting boss.
CDo not allow the neutral switch
lead to slacken except over the
radiator hose. (except for USA
and CDN)
DPass the neutral switch lead
through the holder. (except for
USA and CDN)
EPass the radiator breather hose
outside the engine bracket and
inside the down tube. Then
pass the radiator breather hose
inside the CDI magneto lead.
FClamp the CDI magneto lead,
radiator breather hose, YPVS
breather hose and neutral
switch lead (except for USA andCDN) to the frame.
GClamp the radiator breather
hose, CDI magneto lead and
neutral switch lead (except for
USA and CDN) to the frame.
HPass the CDI magneto lead,
radiator breather hose and neu-
tral switch lead (except for USA
and CDN) in front of the radiator
hose. Then pass the radiator
breather hose inside the CDI
magneto lead.
IPass the radiator breather hose
and ignition coil lead between
the frame and the radiator (left).
JLocate the clamp ends in the
arrowed range.
KBring the connector cover into
contact with the coupler.
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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
P7-1~23
results of test runs before racing? Are inspection and
maintenance completely done?
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3-39
IGNITION TIMING CHECK
INSP
ADJ
EC372012
IGNITION TIMING CHECK
1. Remove:
9Fuel tank
Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section in the CHAPTER 4.
9Spark plug
9Crankcase cover (left)
2. Attach:
9Dial gauge 1
9Spark plug hole dial stand 2
3. Rotate the magneto rotor 1until the piston
reaches top dead center (TDC). When this
happens, the needle on the dial gauge will
stop and reverse directions even though the
rotor is being turned in the same direction.
4. Set the dial gauge to zero at TDC.
5. From TDC, rotate the rotor clockwise until
the dial gauge indicates that the piston is at
a specified distance from TDC.
6. Check:
9Ignition timing
Punch mark aon rotor should be aligned
with punch mark bon stator.
Not aligned Adjust.
Dial gauge:
YU-3097/90890-01252
Spark plug hole dial stand:
YU-1256
Ignition timing (B.T.D.C.):
0.18 mm (0.007 in)
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3-40
IGNITION TIMING CHECK
INSP
ADJ
7. Adjust:
9Ignition timing
Adjustment steps:
9Loosen the screws (stator) 1.
9Align the punch mark on the rotor with
punch mark on the stator 2by moving the
stator.
9Tighten the screws (stator).
Screw (stator):
7 Nm (0.7 m•kg, 5.1 ft•lb)
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4-58
CDI MAGNETOENG
5. Tighten:
9Screw (stator) 1
6. Check:
9Ignition timing
Re-check the ignition timing.
3. Install:
9Plain washer 1
9Nut (rotor) 2
Use the rotor holding tool 3.
4. Adjust:
9Ignition timing
Refer to “IGNITION TIMING CHECK” sec-
tion in the CHAPTER 3. 2. Install:
9Woodruff key 1
9Rotor 2
NOTE:
9Clean the tapered portions of the crankshaft
and rotor.
9When installing the woodruff key, make sure
that its flat surface ais in parallel with the
crankshaft center line b.
9When installing the rotor, align the keyway cof
the rotor with the woodruff key.
7 Nm (0.7 m•kg, 5.1 ft•lb)
Rotor holding tool:
YU-1235/90890-01235
Ignition timing (B.T.D.C.):
0.18 mm (0.007 in)
56 Nm (5.6 m•kg, 40 ft•lb)
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