coil YAMAHA WR 450F 2006 User Guide

4 - 79
ENGAC MAGNETO AND STARTER CLUTCH
AC MAGNETO AND STARTER CLUTCH
Extent of removal:
1 Starter clutch/wheel gear removal
2 Rotor removal
3 Pickup coil/stator removal
Extent of removal Order Part name Q’ty Remarks
AC MAGNETO AND STATOR
REMOVAL
Preparation for removal Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.
Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Bolt [radiator (left)]
Disconnect the AC magneto lead.Refer to “RADIATOR” section.
1 Shift pedal 1
2 Engine guard (left) 1
3 Cover (torque limiter) 1
4 Torque limiter 1 Do not disassemble.
5 Crankcase cover (left) 1
6 Gasket 1
13

4 - 80
ENGAC MAGNETO AND STARTER CLUTCH
NOTE:
Tighten the rotor nut to 65 Nm (6.5 m  kg, 47 ft  lb), loosen and retighten the rotor nut to 65 Nm
(6.5 m  kg, 47 ft  lb).
Extent of removal Order Part name Q’ty Remarks
7 Dowel pin 2
8 Idle gear 1
9 Bearing 1
10 Shaft 1
11* Nut (rotor) 1 Refer to NOTE.
12 Rotor 1 Use special tool.
Refer to “REMOVAL POINTS”.
13 Woodruff key 1
14 Starter clutch 1
15 Starter clutch drive gear 1
16 Holder 1
17 Pick-up coil 1
18 Stator 1
3
3
2
1

4 - 82
ENGAC MAGNETO AND STARTER CLUTCH
Starter clutch
1. Check:
Starter clutch
Damage/wear → Replace.
2. Check:
Idle gear
Idle gear shaft
Starter clutch gear
Pitting/burrs/chips/roughness/wear →
Replace the defective parts.
3. Check:
Starter clutch operation
Install the starter clutch drive gear 1 onto
the starter clutch 2 and hold the starter
clutch.
When turning the starter clutch drive gear
counterclockwise É, the starter clutch and
the starter clutch drive gear should
engage. If the starter clutch drive gear and
starter clutch do not engage, the starter
clutch is faulty and must be replaced.
When turning the starter clutch drive gear
clockwise È, it should turn freely.
If the starter clutch drive gear does not
turn freely, the starter clutch is faulty and
must be replaced.
Torque limiter
1. Check:
Torque limiter
Damage/wear → Replace.
EC4L5000
ASSEMBLY AND INSTALLATION
AC magneto and starter clutch
1. Install:
Stator 1
Bolt (stator) 2
Pick-up coil 3
Bolt (pick-up coil) 4
NOTE:
Pass the AC magneto lead 5 under the pick-
up coil.
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

4 - 83
ENGAC MAGNETO AND STARTER CLUTCH
2. Install:
Holder 1
Bolt 2
NOTE:
Pass the pick-up coil lead 3 and AC mag-
neto lead 4 under the holder as shown.
Take care not to catch the AC magneto lead
between crankcase cover ribs.
Apply the sealant to the grommet of the AC
magneto lead.
Quick gasket®:
ACC-QUICK-GS-KT
YAMAHA Bond No. 1215:
90890-85505
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
3. Install:
Starter clutch drive gear 1
Starter clutch 2
NOTE:
Apply the engine oil on the starter clutch drive
gear inner circumference.
4. Install:
Woodruff key 1
Rotor 2
NOTE:
Clean the tapered portions of the crankshaft
and rotor.
When installing the woodruff key, make sure
that its flat surface a is in parallel with the
crankshaft center line b.
When installing the rotor, align the keyway c
of the rotor with the woodruff key.
c
2 1 1
ba

4 - 87
ENGENGINE REMOVAL
Extent of removal:
1 Engine removal
Extent of removal Order Part name Q’ty Remarks
Ignition coil
Disconnect the AC magneto lead.
Crankcase cover (left) Refer to “AC MAGNETO AND
STARTER CLUTCH” section for remov-
ing the starter motor lead.
Disconnect the starter motor
lead.Refer to “ELECTRIC STARTING SYS-
TEM” section in the CHAPTER 6.
Negative battery lead Disconnect at the starter motor side.
1 Engine skid plate (front) 1
2 Neutral switch 1
3 Oil hose 2
4 Chain cover 1
5 Nut (drive sprocket) 1
Refer to “REMOVAL POINTS”. 6 Lock washer 1
7 Drive sprocket 1
8Clip 1
9 Bolt (brake pedal) 1
10 Brake pedal 1
1

6 - 1
–+ELECELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC600000
ELECTRICAL
EC610000
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
EC611000
ELECTRICAL COMPONENTS
1Headlight
2Multi-function display
3“ENGINE STOP” but-
ton
4Clutch switch
5Diode
6Starter relay diode
7TPS (throttle posi-
tion sensor)
8Starter relay
9Fuse
0Starting circuit cut-off
relayATaillight
BNeutral switch
CStarter motor
DAC magneto
ERectifier/regulator
FIgnition coil
GSpark plug
HStart switch
IMain switch
JCDI unit
KSpeed sensor
LBatteryCOLOR CODE
B ...................... Black
Br ..................... Brown
Ch .................... Chocolate
Dg .................... Dark green
Gy .................... Gray
L....................... Blue
O ...................... Orange
R ...................... Red
Sb .................... Sky blue
W ..................... White
EC612000
WIRING DIAGRAM
FGH
I
J
K
L
1 234
56
789
0A
B C
D E
B/L
W
W
R
BR/BBr
R
BR/BBr
R
Y
Y
L/R/BBB
SbL/W
L/YBBB
WY
RY
R
LY
B
YLB/L
B
B
ON
OFF
10A
BB
OFF
START
R-BrL/W
B
BrL/W
BrL/W
L/B
-Y
Y
B
LY
B
L/WSb
B/WBBB
W/R/W
R/
BGyBrL/W
ON
STOP
O
LSbB/L
W RBrB/W
L
/
BGyWR
/B
B O
L/YSbL/R
R W
Y W
Y W
Y
L B
B
B
RRR/B
B Br B
B B B B
L/W
R
R
R R B
R
BrBr
L/W L/
W
Br B
L/B
L/B
L/R

Br
R/B
L/B L
/W
B/W
WW
/RW
RO
L
Y
ELO
B
L
Y
B/LSb*1
Sb
*2B/W
B
B
L/R L/Y L/Y
B
SbSbL/W
B
Gy
SbBB/LYO
L
*2
O B
L YL/W
B/L
*1
D
E
CI
6
H4 5
B3J
K
2FG
7
8L9
1A
*2
*1
W
B
R/W
Ch
Dg
Y
B BrRW
WRB/W
SIGNAL
+
Backup
SLCT1
SLCT2
RST
GND
BrR/WB
B
R/WBr
WRB/W
R B
W
ChDgYB
B/WWRB/WWR
0
R
W
W W
L/WB/L
Y B
RB
B
L
L
*1: For USA
*2: Except for USA
Y ...................... Yellow
B/L ................... Black/Blue
B/W .................. Black/White
L/B ................... Blue/Black
L/R ................... Blue/Red
L/Y ................... Blue/Yellow
L/W .................. Blue/White
R/B................... Red/Black
R/W.................. Red/White

–+ELEC
6 - 2
MAP-CONTROLLED CDI UNIT
MAP-CONTROLLED CDI UNIT
A map-controlled, CDI ignition system is used in the WR450F.
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.
Throttle position sensorCDI unitIgnition coil
Pickup coilAC magneto rotor

Function of Component
Component Function
TPS
(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 TPS 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)
Ignition timing
Th
rot
t
le
o
peni
ngRev
o
lut
io
ns

–+ELEC
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.
*1 marked: Refer to “FUSE INSPECTION” section in the CHAPTER 3.
*2 marked: Refer to “BATTERY INSPECTION AND CHARGING” section in the CHAPTER 3.
*3 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:
90890-06754Pocket tester:
YU-3112-C/90890-03112
*1 Check fuse.Replace fuse and
check wire harness.
*2 Check battery Recharge or replace.
Spark gap test*3 Clean or replace
spark plug.
Check entire ignition
system for connection.
(couplers, leads and
ignition coil)Repair or replace.
Check “ENGINE STOP”
button.Replace.
Check main switch. Replace.
Check ignition coil. Primary coil Replace.
Secondary coil Replace.
Check AC magneto. Pick-up coil Replace.
Check neutral switch. Repair or replace.
Replace CDI unit.
OK
OK
No spark
OK
OK
OK
OK
OK
OK
Spark No good
No good
No good
No good
No good No good
No good
No good
No good

6 - 4
–+ELECIGNITION SYSTEM
SPARK GAP TEST
1. Disconnect the ignition coil from spark
plug.
2. Remove the ignition coil cap.
3. Connect the dynamic spark tester 1 (igni-
tion checker 2) as shown.
•Ignition coil 3
•Spark plug 4
ÈFor USA and CDN
ÉExcept for USA and CDN
4. Kick the kickstarter.
5. Check the ignition spark gap.
6. Start engine, and increase spark gap until
misfire occurs. (for USA and CDN only)
Minimum spark gap:
6.0 mm (0.24 in)
È
É
COUPLERS, LEADS AND IGNITION COIL
CONNECTION INSPECTION
1. Check:
•Couplers and leads connection
Rust/dust/looseness/short-circuit →
Repair or replace.
•Ignition coil and spark plug as they are fit-
ted
Push in the ignition coil until it closely
contacts the spark plug hole in the cylin-
der head cover.
EC625001
“ENGINE STOP” BUTTON INSPECTION
1. Inspect:
•“ENGINE STOP” button conduct
No continuity while being pushed → Replace.
Continuity while being freed → Replace.
2. Inspect:
•Rubber part
a
Tears/damage → Replace. Tester (+) lead
→ Black lead
1
Tester (–) lead
→ Black lead
2
B
1 B
2 Tester selec-
tor position
PUSH IN
Ω
×
×× × 1
FREE
a

6 - 5
–+ELECIGNITION SYSTEM
MAIN SWITCH INSPECTION
1. Inspect:
•Main switch conduct
Continuous while the main switch is moved to
“OFF” → Replace.
Not continuous while the main switch is moved
to “ON” → Replace.
2. Inspect:
•Main switch indicator light
Use 12 V battery.
Indicator light does not come on → Replace.
3. Inspect:
•Rubber part a
Tears/damage → Replace. Tester (+) lead
→ Red lead
1
Tester (–) lead
→ Brown lead
2
R
1 Br
2 Tester selec-
tor position
ON
Ω
×
×× × 1
OFF
Battery (+) lead
→ Red/Black lead
1
Battery (–) lead
→ Black lead
2
a
EC626002
IGNITION COIL INSPECTION
1. Remove the ignition coil cap.
2. Inspect:
•Primary coil resistance
Out of specification → Replace.
Tester (+) lead
→ Orange lead
1
Tester (–) lead
→ Black lead
2
Primary coil
resistanceTester selector
position
0.08 ~ 0.10
Ω at
20 °C (68 °F)Ω
× 1