2006 YAMAHA YZ250LC ad blue

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)…
1P8-9-31-2 5/19/05 10:30 AM Page 13

EC600000
ELECTRICAL
EC610000
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC611000
ELECTRICAL COMPONENTS
1CDI unit
2“ENGINE STOP” button
3Ignition coil
4TPS (throttle position sensor)
5Solenoid valve
6Neutral switch (Except for USA and CDN)
7CDI magneto
8Spark plug
EC612000
WIRING DIAGRAM
6-1
ELECTRICAL COMPONENTS AND WIRING DIAGRAMELEC
COLOR CODE
B...................Black
L ...................Blue
O ..................Orange
R ..................Red
Sb.................Sky blue
Y...................YellowB/L................Black/Blue
B/R ...............Black/Red
B/W ..............Black/White
G/L ..............Green/Blue
G/W ..............Green/White
W/L...............White/Blue
W/R ..............White/Red
*1:Except for USA and CDN
1P8-9-31-6 5/12/05 10:25 AM Page 2

6-5
IGNITION SYSTEMELEC
2. Inspect:
9Source coil 1 resistance
Out of specification Replace.
Tester (+) leadBlack/Red lead 1
Tester (–) lead
Blacklead 2
Source coil 1 Tester selector
resistance position
720~1,080Ωat
Ω× 100
20°C (68°F)
EC62B000
SPARK PLUG CAP INSPECTION
1.Inspect:
9Spark plug cap
Loose connection Tighten.
Deteriorated/Damaged Replace.
9Spark plug cap resistance
Out of specification Replace.
Tester (+) leadSpark plug lead terminal1
Tester (–) lead
Spark plug terminal2
Spark plug cap Tester selector
resistance position
4~6kΩat
kΩ× 1
20°C (68°F)
EC627011
CDI MAGNETO INSPECTION
1. Inspect:
9Pick-up coil resistance
Out of specification Replace.
Tester (+) leadWhite/Red lead 1
Tester (–) lead
White/Blue lead 2
Pick–up coil Tester selector
resistance position
248~372Ωat
Ω× 100
20°C (68°F)
1P8-9-31-6 5/12/05 10:25 AM Page 12

6-6
IGNITION SYSTEMELEC
3. Inspect:
9Source coil 2 resistance
Out of specification Replace.
Tester (+) leadGreen/Blue lead 1
Tester (–) lead
Green/White lead 2
Source coil 2 Tester selector
resistance position
44~66Ωat
Ω× 10
20°C (68°F)
EC628000
CDI UNIT INSPECTION
Check all electrical components. If no fault is
found, replace the CDI unit. Then check the
electrical components again.
NEUTRAL SWITCH INSPECTION
1. Inspect:
9Neutral switch conduct
No continuous while in neutralReplace.
Continuous while in gearReplace.
Tester (+) leadSky blue lead 1
Tester (–) lead
Ground 2
SbGround
12
NEUTRAL
IN GEAR
Tester selec-
tor position
Ω× 1
1P8-9-31-6 5/12/05 10:25 AM Page 14

6-10
TPS (THROTTLE POSITION SENSOR) SYSTEMELEC
L
Y
B1
21
2
EC624000
COUPLERS AND LEADS CONNECTION
INSPECTION
1. Check:
9Couplers and leads connection
Rust/ Dust/ Looseness/Short-circuit 
Repair or replace.
EC692000
TPS COIL INSPECTION
1. Remove:
9Carburetor
9Mixing chamber top
Refer to “CARBURETOR AND REED
VALVE” section in the CHAPTER 4.
2. Inspect:
9TPS coil resistance
Out of specification Replace.
Tester (+) leadBluelead 1
Tester (–) lead
Blacklead 2
TPS coil Tester selector
resistance position
4~6kΩat
kΩ×1
20°C (68°F)
EC69A000
HANDLING NOTE
cC
Do not loosen the screws {TPS (throttle
position sensor)} except when changing
the TPS (throttle position sensor) due to
failure because it will cause a drop in
engine performance.
1P8-9-31-6 5/12/05 10:25 AM Page 26

6-14
TPS (THROTTLE POSITION SENSOR) SYSTEMELEC
EC694000
TPS INPUT VOLTAGE INSPECTION
1. Disconnect the TPS coupler.
2. Start the engine.
3. Inspect:
9TPS input voltage
Out of specification Replace the CDI
unit.
Tester (+) leadBluelead 1
Tester (–) lead
Black/Bluelead 2
TPS input Tester selector
voltage position
4~6V DCV-20
1P8-9-31-6 5/12/05 10:25 AM Page 34

7-20
SETTINGTUN
EC72Q011
Rear shock absorber setting parts
9Rear shock spring 1
[Equal-pitch steel spring ]
[Equal-pitch titanium spring ]
[Unequal-pitch steel spring ]
cC
Install the spring seat 2to the titanium
spring.
NOTE:
9The unequal-pitch spring is softer in initial char-
acteristic than the equal-pitch spring and is diffi-
cult to bottom out under full compression.
9The I.D. color ais marked at the end of the
spring.
SPRING SPRINGI.D.SPRING
TYPE
RATE PART NUMBERCOLORFREE
/POINTLENGTH
SOFT 4.3 5UN-22212-00Brown/1260
5.3 5UN-22212-50
Yellow/1260
5.5 5UN-22212-60 Pink/1 260
STIFF 5.7 5UN-22212-70 White/1 260
SPRING
SPRINGI.D.SPRING
TYPE RATE
PART NUMBERCOLORFREE
(approx.)/POINTLENGTH
SOFT 4.5 5UN-22212-A0 Green/2 275
4.7 5UN-22212-B0 Red/2 275
4.9 5UN-22212-C0 Black/2 275
5.1 5UN-22212-D0 Blue/2 275
5.3 5UN-22212-E0
Yellow/2 275
5.5 5UN-22212-F0 Pink/2 275
STIFF 5.7 5UN-22212-G0
White/2 275
SPRING
TYPESPRING SPRING I.D.FREE
RATE PART NUMBER COLORLENGTH
(approx.)
SOFT4.5 1C3-22212-00Green265
4.7 1C3-22212-10Red265
STD 4.9 1C3-22212-20 Black 265
STIFF 5.1 1C3-22212-30 Blue 265
1P8-9-31-7 5/19/05 1:31 PM Page 44