Service manual
Table Of Contents
- Inroduction
- Yamaha Motor Corporation, USA YZ/WR Motorcycle Limited Warranty
- How to use this Manual
- Index
- Contents
- Chapter 1 General Information
- Chapter 2 Specifications
- Chapter 3 Regular Inspection and Adjustments
- Chapter 4 Engine
- Seat, Fuel Tank and Side Covers
- Exhaust Pipe and Silencer
- Radiator
- Carburetor and Reed Valve
- Cylinder Head, Cylinder and Piston
- Clutch and Primary Driven Gear
- Kick Axle, Shift Shaft and Primary Drive Gear
- YPVS Govenor
- Water Pump
- CDI Magneto
- Engine Removal
- Crankcase and Crankshaft
- Transmission, Shift Cam and Shift Fork
- Chapter 5 Chassis
- Chapter 6 Electrical
- Chapter 7 Tuning
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3-38
ELECTRICAL/SPARK PLUG INSPECTION
INSP
ADJ
EC370000
ELECTRICAL
EC371001
SPARK PLUG INSPECTION
1. Remove:
9
Spark plug
2. Inspect:
9
Electrode 1
Wear/Damage → Replace.
9
Insulator color 2
Normal condition is a medium to light tan
color.
Distinctly different color → Check the
engine condition.
NOTE:
When the engine runs for many hours at low
speeds, the spark plug insulator will become
sooty, even if the engine and carburetor are in
good operating condition.
3. Measure:
9
Plug gap a
Use a wire gauge or thickness gauge.
Out of specification → Regap.
4. Clean the plug with a spark plug cleaner if
necessary.
5. Tighten:
9
Spark plug
NOTE:
9
Before installing a spark plug, clean the
gasket surface and plug surface.
9
Finger-tighten a the spark plug before torquing
to specification b.
Spark plug gap:
0.5~0.6 mm (0.020~0.024 in)
Standard spark plug:
BR9EG/NGK (resistance type)
20 Nm (2.0 m•kg, 14 ft•lb)
1C3-28199-10 87 04.5.17, 9:21:11 PM