2006 YAMAHA WR 450F oil

6 - 12
–+ELECELECTRIC STARTING SYSTEM
STARTER MOTOR
0
9
56
7
5 0 8
9
4
3
2
1
New
New
New
B
5
1
Extent of removal:
1 Starter motor disassembly
Extent of removal Order Part name Q’ty Remarks
STARTER MOTOR REMOVAL
Preparation for removal Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.
Crankcase cover (left) Refer to “AC MAGNETO AND
STARTER CLUTCH” section in the
CHAPTER 4.
1 Starter motor 1
STARTER MOTOR DISASSEM-
BLY
1 Starter motor front cover 1
2 Washer (starter motor front
cover)1
3 Plain washer 1
4 Circlip 1
5 O-ring 3
1

–+ELEC
6 - 17
CHARGING SYSTEM
EC680000
CHARGING SYSTEM
EC681001
INSPECTION STEPS
If the battery is not charged, use the following inspection steps.
*1 marked: Refer to “FUSE INSPECTION” section in the CHAPTER 3.
*2 marked: Refer to “BATTERY INSPECTION AND CHARGING” section in the CHAPTER 3.
NOTE:
•Remove the following parts before inspection.
1) Seat
2) Fuel tank
•Use the following special tool in this inspection.
Pocket tester:
YU-3112-C/90890-03112
*1 Check fuse.Replace fuse and
check wire harness.
*2 Check battery. Recharge or replace.
Check each coupler and
wire connection.Repair or replace.
Check charging voltage.Charging system is
good.
Check AC magneto. Charging coil Replace.
Replace rectifier/regulator.
OK
OK
OK
No good
OK
No good
No good No good
No good OK

6 - 18
–+ELECCHARGING SYSTEM
EC624000
COUPLERS AND LEADS CONNECTION
INSPECTION
1. Check:
•Couplers and leads connection
Rust/dust/looseness/short-circuit →
Repair or replace.
CHARGING VOLTAGE INSPECTION
1. Start the engine.
2. Inspect:
•Charging voltage
Out of specification → If no failure is
found in checking the source coil resis-
tance, replace the rectifier/regulator.
Tester (+) lead
→ Red lead
1
Tester (–) lead
→ Black lead
2
Charging
voltageTester selector
position
14.1 ~ 14.9 V at
5,000 r/minDCV-20
R
BW Y1
2
3. Inspect:
•Charging coil resistance
Out of specification → Replace.
Tester (+) lead
→ White lead
1
Tester (–) lead
→ Ground
2
Charging coil
resistanceTester selector
position
0.288 ~ 0.432
Ω
at 20 °C (68 °F)Ω
× 1

–+ELEC
6 - 19
TPS (THROTTLE POSITION SENSOR) SYSTEM
EC690000
TPS (THROTTLE POSITION SENSOR) SYSTEM
INSPECTION STEPS
If the TPS will not operate, use the following inspection steps.
NOTE:
Use the following special tools in this inspection.
Pocket tester:
YU-3112-C/90890-03112
Check entire ignition
system for connection.Repair or replace.
Check TPS. TPS coil Replace.
Check CDI unit.TPS input
voltageReplace.
OK
OK
No good
No good
No good

6 - 20
–+ELECTPS (THROTTLE POSITION SENSOR) SYSTEM
HANDLING NOTE
CAUTION:
Do not loosen the screws {TPS (throttle
position sensor)}
1 except when changing
the TPS (throttle position sensor) due to
failure because it will cause a drop in
engine performance.
1
EC624000
COUPLERS AND LEADS CONNECTION
INSPECTION
1. Check:
•Couplers and leads connection
Rust/dust/looseness/short-circuit →
Repair or replace.
TPS COIL INSPECTION
1. Inspect:
•TPS coil resistance
Out of specification → Replace.
2. Loosen:
•Throttle stop screw 1
NOTE:
Turn out the throttle stop screw until the throt-
tle shaft is in the full close position.Tester (+) lead
→ Blue lead
1
Tester (–) lead
→ Black lead
2
TPS coil
resistanceTester selector
position
4 ~ 6 kΩ at
20 °C (68 °F)kΩ × 1

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–+ELECTPS (THROTTLE POSITION SENSOR) SYSTEM
3. Inspect:
•TPS coil variable resistance
Check that the resistance in increased as
the throttle grip is moved from the full
close position to the full open position.
Out of specification → Replace.
Tester (+) lead
→ Yellow lead
1
Tester (–) lead
→ Black lead
2
TPS coil variable
resistanceTester selec-
tor position
Full closed Full opened
k
Ω
× 1 0 ~ 2 k
Ω
at 20 °C
(68°F)4 ~ 6 k
Ω
at 20 °C
(68°F)
TPS REPLACEMENT AND ADJUSTMENT
1. Remove:
•TPS coupler
•Screw (TPS) 1
•TPS 2
NOTE:
Loosen the screws (TPS) using the T25 bit.
2. Replace:
•TPS
3. Install:
•TPS 1
•Screw (TPS) 2
•TPS coupler
NOTE:
•Align the slot a in the TPS with the projec-
tion b on the carburetor.
•Temporarily tighten the screws (TPS).
12
21
b
a

–+ELEC
6 - 24
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 AC magneto. Lighting coil Replace.
Check the entire lighting
system proper for connec-
tions.Repair or replace.
Check the rectifier/regulator.Out-put
voltageReplace.
Pocket tester:
YU-3112-C/90890-03112
OK
OK
OK
No good
Improperly connectedNo good
No good

6 - 25
–+ELECLIGHTING SYSTEM
AC MAGNETO INSPECTION
1. Inspect:
•Lighting coil resistance
Out of specification → Replace.
RECTIFIER/REGULATOR INSPECTION
1. Connect the battery leads.
2. Start the engine.
3. Turn on the headlight and taillight by turn-
ing on the lights switch.
4. Inspect:
•Out-put voltage
Out of specification → Replace rectifier/
regulator. Tester (+) lead
→ Yellow lead
1
Tester (–) lead
→ Ground
2
Lighting coil
resistanceTester selector
position
0.224 ~ 0.336
Ω
at 20 °C (68 °F)Ω
× 1
Tester (+) lead
→ Yellow lead
1
Tester (–) lead
→ Black lead
2
Out-put voltageTester selector
position
13.0 ~ 14.0 V at
5,000 r/minACV-20
R
BW
Y1
2