magneto YAMAHA WR 250F 2002 Owner's Manual

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ENGCRANKCASE AND CRANKSHAFT
CRANKCASE AND CRANKSHAFT
Extent of removal:1 Crankcase separation2 Crankshaft removal
Extent of removal Order Part name Q’ty Remarks
CRANKCASE AND CRANK-
SHAFT REMOVAL
Preparation for removal Engine Refer to “ENGINE REMOVAL” section.
Piston Refer to “CYLINDER AND PISTON” sec-
tion.
Kick shaft assembly
Refer to “KICK SHAFT AND SHIFT
SHAFT” section.
Segment
Stator Refer to “CDI MAGNETO” section.
Balancer shaft Refer to “BALANCER” section.
1 Timing chain guide (intake side) 1
2 Timing chain 1
3Oil delivery pipe 2
1
21

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ELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC600000
ELECTRICAL
EC610000
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC611000
ELECTRICAL COMPONENTS
1
Headlight
2
Voltage regulator
3
Engine stop switch
4
Throttle position sensor
5
Taillight
6
Neutral switch
7
CDI magneto
8
Spark plug
9
Ignition coil
0
Light switch
A
CDI unit
COLOR CODE
B...................... Black
Br .................... Brown
G ..................... Green
Gy ................... Gray
L ...................... Blue
O ..................... Orange
P...................... Pink
R ..................... Red
Sb.................... Sky blue
EC612000
WIRING DIAGRAM
B/L
R/WL/W
LY
L
Y
B
1B L
YYLB
5LB
YBLB
LB
2
6
4 9
8
W
R Br
G PB/YP
B Br
G W
R
O
L Y B/LSbSb
B/L Y O
L
A
Y
Br
Gy
PGR
WB
L YL Y
B B/L
SbW
Sb
WL/W
R/WL/WSbR/WSb
W
O
B
0
7
BGyBGy
Y
BL
B
B
3B/WBB/WG/B
L
B YLB Y

W ..................... White
Y ...................... Yellow
B/L ................... Black/Blue
B/W .................. Black/White
B/Y ................... Black/Yellow
G/B................... Green/Black
L/W .................. Blue/White
R/W .................. Red/White

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COMPOSANTS ELECTRIQUES ET SCHEMA DE CABLAGE
ELEKTRISCHE BAUTEILE UND SCHALTPLAN
COMPONENTI ELETTRICI E SCHEMA DI CABLAGGIO
ELEKTRISCHE
ANLAGE
ELEKTRISCHE BAUTEI-
LE UND SCHALTPLAN
ELEKTRISCHE BAUTEILE
1
Scheinwerfer
2
Spannungsregulator
3
Motorstoppschalter
4
Drosselklappensensor
5
Rücklicht
6
Leerlaufschalter
7
CDI-Schwungradmagnetzünder
8
Zündkerze
9
Zündspule
0
Lichtschalter
A
CDI-Zündbox
FARB-KODIERUNG
B ............................ schwarz
Br ........................... braun
G ............................ grün
Gy .......................... gran
L ............................. blau
O ............................ orange
P ............................ rosa
R ............................ rot
Sb .......................... hellblau
W ........................... weiß
Y ............................ gelb
B/L ......................... schwarz/blau
B/W ........................ schwarz/weiß
B/Y ......................... schwarz/gelb
G/B......................... grün/schwarz
L/W ........................ blau/weiß
R/W ........................ rot/weiß
SCHALTPLAN
* Nicht USA
PARTIE
ELECTRIQUE
COMPOSANTS ELECTRI-
QUES ET SCHEMA DE
CABLAGE
COMPOSANTS ELECTRIQUES
1
Phare
2
Régulateur de tension
3
Couper-circuit du moteur
4
Capteur de papillon des gaz
5
Feu arrière
6
Contacteur de point mort
7
Magnéto CDI
8
Bougie
9
Bobine d’allumage
0
Contacteur d’éclairage
A
Bloc CDI
CODE DE COULEUR
B............................ Noir
Br .......................... Brun
G ........................... Vert
Gy ......................... Gris
L ............................ Bleu
O ........................... Orange
P ............................ Rose
R............................ Rouge
Sb .......................... Bleu ciel
W........................... Blanc
Y ........................... Jaune
B/L ........................ Noir/Bleu
B/W ....................... Noir/Blanc
B/Y........................ Noir/Jaune
G/B........................ Vert/Noir
L/W ....................... Bleu/Blanc
R/W ....................... Rouge/Blanc
SCHEMA DE CABLAGE
* Excepté pour USA
6 - 1
IMPIANTO
ELETTRICO
COMPONENTI ELET-
TRICI E SCHEMA DI
CABLAGGIO
COMPONENTI ELETTRICI
1
Faro
2
Regolatore di tensione
3
Interruttore di arresto motore
4
Sensore di posizione valvola a far-
falla
5
Fanalino posteriore
6
Interruttore folle
7
Magnete CDI
8
Candela d’accensione
9
Bobina di accensione
0
Interruttore luci
A
Unità CDI
CODICE COLORE
B ................................nero
Br ...............................marrone
G ................................verde
Gy ..............................grigio
L ................................blu
O ................................arancione
P.................................rosa
R ................................rosso
Sb...............................azzurro
W ...............................bianco
Y ................................giallo
B/L.............................nero/blu
B/W ...........................nero/bianco
B/Y ............................nero/giallo
G/B ............................verde/nero
L/W............................blu/bianco
R/W ...........................rosso/bianco
SCHEMA DI CABLAGGIO
*Tranne USA





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6 - 2
MAP-CONTROLLED CDI UNIT
MAP-CONTROLLED CDI UNIT
A map-controlled, CDI ignition system is used in the WR250F.
The microcomputer in the CDI unit detects the engine speed and throttle position, thus determining
the optimum ignition timing through the entire operating range. In this way, quick throttle response
can be achieved according to various riding conditions.
CDI unit
Throttle position sensor
Pickup coil CDI magneto rotorIgnition coil


Function of Component

Component Function
Throttle position sensor Detects throttle valve opening and inputs it into the computer in the
CDI unit as a throttle opening signal.
Pickup coil Detects signal rotor revolutions and inputs them into the computer in
the CDI unit as engine revolution signals.
CDI unit The signals of the throttle position sensor and pickup coil sensor are
analyzed by the computer in the CDI unit, which then adjusts ignition
timing for the operation requirements.

Principal of 3-Dimensional Control
Conventionally, ignition timing was controlled only
by engine revolutions (2-dimensional control).
However, ignition timing needs advancement also
by engine load. Thus, accurate ignition timing can
be determined by adding throttle opening to deter-
mine ignition timing (3-dimensional control).
3-D Image Map of Ignition Timing
(different from actual characteristics)
Revolutions
Ignition timing
Throttle opening

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6 - 3
IGNITION SYSTEM
EC620000
IGNITION SYSTEM
INSPECTION STEPS
Use the following steps for checking the possibility of the malfunctioning engine being attributable to
ignition system failure and for checking the spark plug which will not spark.
*marked: Only when the ignition checker is used.
NOTE:


Remove the following parts before inspection.
1) Seat
2) Fuel tank

Use the following special tools in this inspection.
Dynamic spark tester:
YM-34487
Ignition checker:
90890-06754
Pocket tester:
YU-3112-C/90890-03112
Spark gap test*Clean or replace
spark plug.
Check entire ignition
system for connection.Repair or replace.
Check engine stop switch. Replace.
Check ignition coil. Primary coil Replace.
Secondary coil Replace.
Check CDI magneto. Pickup coil Replace.
Charging coil Replace.
Check neutral switch. Repair or replace.
Replace CDI unit.
No spark
OK
OK
OK
OK
OK
Spark
No good
No good
No good
No good
No good
No good
No good

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IGNITION SYSTEM
EC626002
IGNITION COIL INSPECTION
1. Inspect:

Primary coil resistance
Out of specification
→
Replace.
Tester (+) lead
→
Orange lead
1
Tester (–) lead → Black lead 2
Primary coil
resistanceTester selector
position
0.20 ~ 0.30 Ω at
20 ˚C (68 ˚F)Ω × 1
2. Inspect:
Secondary coil resistance
Out of specification → Replace.
NOTE:
When inspecting the secondary coil resis-
tance, remove the spark plug cap.
CDI MAGNETO INSPECTION
1. Inspect:
Pickup coil resistance
Out of specification → Replace. Tester (+) lead → Spark plug lead 1
Tester (–) lead → Orange lead 2
Secondary coil
resistanceTester selector
position
9.5 ~ 14.3 kΩ at
20 ˚C (68 ˚F)kΩ × 1
Tester (+) lead → Red lead 1
Tester (–) lead → White lead 2
Pickup coil
resistanceTester selector
position
248 ~ 372 Ω at
20 ˚C (68 ˚F)Ω × 100

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6 - 7
THROTTLE POSITION SENSOR SYSTEM
THROTTLE POSITION SENSOR SYSTEM
INSPECTION STEPS
If the throttle position sensor will not operate, use the following inspection steps.
*marked: Refer to “IGNITION SYSTEM” section.
NOTE:
Use the following special tools in this inspection.
Pocket tester:
YU-3112-C/90890-03112Inductive tachometer:
YU-8036-B
Engine tachometer:
90890-03113
Check entire ignition
system for connection.Repair or replace.
Check throttle position
sensor.Throttle posi-
tion sensor coilReplace.
*Check CDI magneto. Charging coil Replace.
Check CDI unit.Throttle posi-
tion sensor
input voltageReplace.
OK
OK
OK
No good
No good
No good
No good

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6 - 12
LIGHTING SYSTEM
LIGHTING SYSTEM
INSPECTION STEPS
Refer to the following flow chart when inspecting the ignition system for possible problems.
NOTE:
Replace the bulb and/or bulb socket.
1) Seat
2) Fuel tank
Use the following special tool.
Check the bulb and bulb
socket.Replace the bulb and/
or bulb socket.
Check the light switch. Replace.
Check the CDI magneto. Lighting coil Replace.
Check the entire lighting sys-
tem proper for connections.Repair or replace.
Check the voltage regula-
tor.Out-put volt-
ageReplace.
Pocket tester:
YU-3112-C/90890-03112Inductive tachometer:
YU-8036-B
Engine tachometer:
90890-03113
OK
OK
OK
OK
No good
No good
Improperly connected
No good
No good

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SYSTEME D’ECLAIRAGE
PROCEDURES DE VERIFICATION
Se référer au tableau suivant lors de l’inspection du système d’allumage lors de pannes.
N.B.:
Déposer les pièces suivantes avant vérification.
1) Selle
2) Réservoir de carburant
Se servir de l’outil spécial suivant.
Contrôler l’ampoule et le culot
d’ampoule.Changer l’ampoule et/ou le
culot d’ampoule.
Contrôler la connexion de tout le
système d’éclairage.Remplacer.
Contrôler la magnéto CDI.Bobine
d’éclairageRemplacer.
Contrôler tout le système d’éclai-
rage au point de vue connexions.Réparer ou remplacer.
Inspecter le régulateur de tension Tension de sortie Remplacer.
Multimètre:
YU-3112-C/90890-03112Compte-tours inductif:
YU-8036-B
Compte-tours moteur:
90890-03113
O.K.
O.K.
O.K.
O.K.
Mauvais
Mauvais
Mauvaise connexion
Mauvais
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SYSTEME D’ECLAIRAGE
Mauvais

6 - 13
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LIGHT SWITCH INSPECTION
1. Inspect:
Light switch continuity
No continuous while being → Replace.
Continuous while being OFF → Replace. Tester (+) lead → Yellow lead 1
Tester (–) lead → Blue lead 2
Y
1L
2Tester selec-
tor position
Ω × 1
OFF
CDI MAGNETO INSPECTION
1. Inspect:
Lighting coil resistance
Out of specification → Replace.
VOLTAGE REGULATOR INSPECTION
1. Start the engine.
2. Turn on the headlight and taillight by turn-
ing on the light switch.
3. Inspect:
Out-put voltage
Out of specification → Replace voltage
regulator. Tester (+) lead → Yellow lead 1
Tester (–) lead → Black lead 2
Lighting coil
resistanceTester selector
position
0.16 ~ 0.24 Ω at
20 ˚C (68 ˚F)Ω × 1
Tester (+) lead → Blue lead 1
Tester (–) lead → Black lead 2
Out-put voltageTester selector
position
13.3 ~ 14.3 V at
5,000 r/minACV-20
BL
1
2
1
2