2005 YAMAHA YZ250LC ignition

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 Bolt90890-01278
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-01442, 90890-01442 Fork seal driver
YM-01442 90890-01442
This tool is used when install the fork oil seal.
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.
YU-3112-C, 90890-03112 Yamaha pocket tester
YM-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: USA, ZA, AUS, NZ EUROPE, CDN
Primary reduction system Gear←
Primary reduction ratio 63/21 (3.000)←
Secondary reduction system Chain drive←
Secondary reduction ratio 50/14 (3.571) 49/14 (3.500)
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, NZEUROPECDN
Frame type Semi double ←←
cradle
Caster angle 26.9° 27.0° 26.9°
Trail115 mm (4.53 in) 117 mm (4.61 in) 116 mm (4.57 in)
Tire:
Type With tube
Size (front) 80/100-21 51M
Size (rear) 110/90-19 62M
Tire 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 8 0.8 5.8
Rotor M12 ×1.25 1 56 5.6 40
Ignition coil M 6 ×1.0 2 7 0.7 5.1
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-10/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 5NX-01/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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2-14
CABLE ROUTING DIAGRAMSPEC
EC240000
CABLE ROUTING DIAGRAM
1Radiator hose
2Throttle cable
3Clutch cable
4“ENGINE STOP” button lead
5Radiator breather hose
6C.D.I. magneto lead
7Ignition coil leadAPass the clutch cable on the out-
side of the throttle cable and
“ENGINE STOP” button lead.
BPass through the cable guide the
throttle cable, “ENGINE STOP”
button lead and clutch cable.
CAlign the throttle cable locating
tape with the cable guide.
DPass above the radiator hose the
throttle cable, “ENGINE STOP”
button lead and clutch cable.
EClamp the “ENGINE STOP” but-
ton lead to the frame.
FClamp to the frame the throttle
cable, clutch cable, TPS (throttle
position sensor) lead and sole-
noid valve lead.
GClamp to the frame the throttle
cable, TPS (throttle position sen-
sor) lead and solenoid valve
lead.HPass the clutch cable in front of
the center of the cylinder head
tightening nut.
IPass the air vent hose, overflow
hose and crankcase breather
hose between the frame and
connecting rod.
JLocate the clamp ends in the
arrowed range.
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2-15
CABLE ROUTING DIAGRAMSPEC
1Clamp
2Radiator hose
3Solenoid valve lead
4TPS (throttle position sensor)
lead
5Air vent hose (left)
6Crankcase breather hose
7Overflow hose
8Air vent hose (right)AInsert the tip of the fuel tank
breather hose into the hole in
the steering shaft cap.
BPass the radiator breather hose,
ignition coil lead and C.D.I.
magneto lead between the
frame and the left of the radia-
tor.
CClamp the C.D.I. magneto lead
and ignition coil lead to the
frame.
DInstall the side core and ignition
coil together to the frame.
EPass the radiator breather hose
from the outside of the engine
bracket to the inside of the
downtube. Pass the radiator
breather hose on the inside of
the C.D.I. magneto lead.
FClamp the C.D.I. magneto lead,
radiator breather hose and
Y.P.V.S. breather hose. GClamp to the frame the radiator
breather hose and C.D.I. mag-
neto lead.
HPass the C.D.I. magneto lead
and radiator breather hose in
front of the radiator hose.
IPass the throttle cable behind
the air vent hose.
JPass the air vent hose, overflow
hose and crankcase breather
hose so that they do not contact
the rear shock absorber.
KClamp the air vent hoses.
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2-16
CABLE ROUTING DIAGRAMSPEC
1Clamp
2High tension cord
3C.D.I.unit
4“ENGINE STOP” button lead
5Ignition coil lead
6Radiator hose
7Radiator breather hose
8Throttle cable
9Clutch cable
0WireharnessAClamp the wireharness to the
right engine bracket.
BPass the high tension cord to
the right of the radiator hose.
CPass the C.D.I. unit lead
between the frame and the right
side of the radiator and then
above the radiator fitting boss.
DPass the radiator breather hose
behind the radiator hose.
ELocate the clamp ends in the
arrowed range.
F
Insert the C.D.I. unit band until it
stops at the C.D.I. unit stay.
1P8-9-30-2 16/6/04 11:47 AM Page 58