1. Check:
- Primary coil resistance
Out of specification → Replace.
Primary coil resistance 0.85-1.15
![](https://motoinstruction.ru/img/yamaha/20/126937.jpg)
a. Remove the ignition coil from the spark plug.
b. Connect the pocket tester (
![](https://motoinstruction.ru/img/yamaha/20/126938.jpg)
Pocket tester 90890-03112.
Analog pocket tester YU-03112-C.
- Positive tester probe. Red/Black "1"
- Negative tester probe. Orange or Gray/Red or Orange/Green or Gray/Green "2"
![](https://motoinstruction.ru/img/yamaha/20/126939.jpg)
c. Measure the primary coil resistance.
2. Check:
- Secondary coil resistance
Out of specification → Replace.
Secondary coil resistance 8.50-11.50 k
![](https://motoinstruction.ru/img/yamaha/20/126940.jpg)
a. Connect the pocket tester (
![](https://motoinstruction.ru/img/yamaha/20/126941.jpg)
Pocket tester 90890-03112.
Analog pocket tester YU-03112-C.
- Negative tester probe. Red/Black "1"
- Positive tester probe. Spark plug terminal "2"
![](https://motoinstruction.ru/img/yamaha/20/126942.jpg)
b. Measure the secondary coil resistance.
3. Check:
- Ignition spark gap
Out of specification → Replace.
Minimum ignition spark gap 6.0 mm (0.24 in)
a. Connect the ignition checker "1" as shown.
Ignition checker 90890-06754.
Opama pet-4000 spark checker YM-34487.
![](https://motoinstruction.ru/img/yamaha/20/126943.jpg)
2. Ignition coil
b. Turn the main switch to "ON" and engine stop switch to "
![](https://motoinstruction.ru/img/yamaha/20/126944.jpg)
c. Measure the ignition spark gap "a".
d. Crank the engine by pushing the start switch "
![](https://motoinstruction.ru/img/yamaha/20/126945.jpg)