GT550 coils, replace or repair?

[Kevgt550]

Hi all,
- 1977 GT550 in the US -
I am diagnosing a misfiring cylinder from the end of last summer, as I just got around to it.
I took off the ignition coils to test (cream colored, Denso coils I think) and got about 4 ohms for all three coils for the primary. I went to do the secondary test and got about 18 k Ohms on the left AND right coils, while I got 8 k Ohms on the middle coil which I believe is the expected value. Weirdly enough, I at first could not get any resistance from the right side coil, and then got 18k once i took them off, yet it was not the cylinder which was misfiring or really having any issues. That was the left one which I am diagnosing.
So I have reason to believe that these very old coils need work or replacement, unfortunately it appears that every coil replacement previously discussed in this forum is no longer being sold as far as I can tell. ( Rex Caunt racing, HVCcycle )
So I am considering either some coils like this:
https://www.ebay.com/itm/273563358418?m ... media=COPY
Or replacing the wires and hoping I can get it right and they work. I did a bit of research on this and think I could do it but would prefer to just do all new if I could.
I'd like to know if anyone has run an alternative coil that is somewhat plug and play, and is still available, or if anyone has any info to share.

[jabcb]

Lots of people are selling coils that look similar to the ones you linked.
You linked branded coils made in Taiwan, which are likely one of the better choices.

Rex’s Speed Shop in the UK has coils. A good bit more expensive.
https://www.rexs-speedshop.com/product/ ... 550-gt750/

[Kevgt550]

Lots of people are selling coils that look similar to the ones you linked.
You linked branded coils made in Taiwan, which are likely one of the better choices.

Rex’s Speed Shop in the UK has coils. A good bit more expensive.
https://www.rexs-speedshop.com/product/ ... 550-gt750/

Wow not sure how i didn’t come across Rex’s speed shop. Though you are right, they are selling a similar product for much more, so i may go with the other one.
Thanks!