XS/XJ ignition coils

[John]

Does anybody know if the secondary (output) voltage on the XJ coils is any higher than that of the XS coils? I have a couple of sets of XJ coils, and I wouldn't mind a hotter spark to go along with the new big bore installation. Any little edge on that FJ1100 sitting next my bike in the garage will be helpful

[bkr]

Hot Coil

Hey John Not sure if XJ coils are hotter but to get a sure edge on the wife's bike see your Suzuki dealer and get a Hayabusa, then you have an EDGE.... LOL bkr

[Jerry]

There is some differences between the XJ and XS coils, mechanical as well as electrical. Here are the stock specs:

XJ Coils:

Model: CM12-09 Hitachi
Min spark gap: 6mm (0.24 in)
Pri winding resistance: 2.5 ohm + or - 20% at 20 deg C (68 deg F)
Secondary winding resistance: 11 Kohm + or - 20% at 20 deg C

XS coils:

Model: CM12-08 Hitachi
Min spark gap: 6mm (0.24 in.)
Pri winding resistance: 1.5 ohm + or - 20% at 20 deg C (68 deg F)
Secondary winding resistance: 15 Kohm + or - 20% at 20 deg C

Note differences in both primary and secondary resistances! Incidently, the XS coils are rated at 19KV, but there is no rating in the specs for the XJ coils.

Upshot: Can't tell by the specs if the XJ coils are 'hotter' than the XS, but they are different electrically. I've been told they are also different mechanically (different size, XJ smaller) but don't have side-by-side comparisons to give you.


Specs are from XJ and '81 H microfiche, section 7, Appendicies.