Coil upgrade

No eBay APP ID and/or Cert ID defined in Kunena configurationJust spotted these on eBay, are they a decent upgrade and will they work on my 79 A1?

710-127635-2958-0

There is a wealth of information on this site regarding ignition coils for the 1300. This thread is a good place to start reading:

www.kz1300.com/index.php/forum/electrica...-z1300-kz1300-how-to

I can’t find the listing on eBay you mentioned.

 

No eBay APP ID and/or Cert ID defined in Kunena configuration

biltonjim wrote:

I can’t find the listing on eBay you mentioned.


 

When I got my bike there was a spare set of coils included. The coils look brand new and I’m a bit suspicious as to why they’ve not been fitted? A quick check with my elektricery meter on the two  thin wires (electrical idiot speak) showed 3ohms. So the question is will these coils be a worthwhile upgrade over the standard ones or would I be better buying the Honda ones? Also will I need to disconnect the ballast resistor dooh dah?
cheers guys 

I guess you don’t know the origin of those coils, so it’s hard to know if anybody has experienced their use on a 1300.  The primary resistance at 3.0 ohms would be fine without the inclusion of the resistor.  The factory manual states that the ignition coils should have primary resistance readings of 1.2 to 1.9 ohm.  The factory fitted resistor should have readings of 1.5 to 1.9 ohm, therefore the combined coil and resistor readings should fall between 2.7 to 3.8 ohm.
Since your coils show 3.0 ohm primary resistance, it should be safe to use them without the resistor.  Too LOW a resistance could result in damage to the transistors in the igniter unit, so you definitely don’t want less than 2.7 ohms.
It would be wise to check the secondary resistance , and for internal shorting to the core.
The factory service manual is well worth downloading, or buy a hard copy .