Ignition Coil Different numbers

[Petew]

I was swapping coils from a known good bike with another that I had determined was bad. One bike has coils with 12VCM-54 and the other has 12VCM-55 on them, are they really different or simply production changes? Both are on 1980 XS400 of the same model.

 

[xschris]

Post a pic of them. Also you can do an ohm test on the to see if they are in spec. That would be the best way to tell if they are good.

 

[Petew]

Post a pic of them. Also you can do an ohm test on the to see if they are in spec. That would be the best way to tell if they are good.

Thanks Chris. I will test them. They are identical save for the number being one digit off, I will post pictures tomorrow and try to find a working multimeter in the house.

 

[Petew]

I finally got a chance to test them with working ohm meter. the best reading I could get was 7.4 at the secondary in 1.9 at the primary. I have replaced them with a set that was in the specified range.