hi Typhoon,
Just after I got my 78 KZ650 C2, I got a boyer system . It lasted for about 6 months I think. Just like you ,mine had power to the Moduale but no spark. I returned it to Partsmore(I think) and they replaced it with a new one, which only Lasted for4 months:angry: . I returned that one for a refund, peeled the sticker off my seat pan voweng never to use that crap again. I now run a Dyna-S and Dyna 3 ohm coils, haven't had a problem for about 8 monthes.
I think you will see that dynas are the crowd favorite here @ KZRider!
Good luck
Mac