2010 YAMAHA WR 450F Owners Manual

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YAMAHA WR 450F 2010  Owners Manual 7-1
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
ELECTRICAL
This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles 
(e.g., Yamaha dealers, ser

Page 210 of 230

YAMAHA WR 450F 2010  Owners Manual 
7-2
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
WIRING DIAGRAM
1. Headlight
2. Multi-function display
3. Engine stop switch
4. Clutch switch
5. Diode
6. Starter relay diode
7. Throttle position sensor
8

Page 211 of 230

YAMAHA WR 450F 2010  Owners Manual 7-3
IGNITION SYSTEM
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 t

Page 212 of 230

YAMAHA WR 450F 2010  Owners Manual 7-4
IGNITION 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" (ignition checker "2") as 
shown.
• Ign

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YAMAHA WR 450F 2010  Owners Manual 7-5
ELECTRIC STARTING SYSTEM
3. Inspect:
• Secondary coil resistance
Out of specification→Replace.
4. Inspect:
• Sealed portion of ignition coil "a"
• Spark plug terminal pin "b"
• Threaded

Page 214 of 230

YAMAHA WR 450F 2010  Owners Manual 7-6
ELECTRIC STARTING SYSTEM
INSPECTION STEPS
If the starter motor will not operate, use the following inspection steps.
*1 marked: Refer to "CHECKING THE FUSE" section in the CHAPTER 3.
*2 marked: Re

Page 215 of 230

YAMAHA WR 450F 2010  Owners Manual 7-7
ELECTRIC STARTING SYSTEM
CHECKING THE COUPLERS AND 
LEADS CONNECTION
1. Check:
• Couplers and leads connection
Rust/dust/looseness/short-circuit
→Repair or replace.
CHECKING THE STARTER 
MOTOR

Page 216 of 230

YAMAHA WR 450F 2010  Owners Manual 7-8
ELECTRIC STARTING SYSTEM
CHECKING THE START SWITCH
1. Inspect:
• Start switch conduction
Not conductive while it is pushed→
Replace.
Conductive while it is freed→Re-
place.
Set the tester se