Honda CBX550 ignition coil problems?

[kevin r]

I have the above motorcyle and one of the ignition coils burnt out. I replaced it with a new one from Honda and it went well for a couple of months. I had it parked on the drive for a number of months while I carried out other repairs. Fired it up and only running on two cylinders (it has four cylinders) again. Traced the HT leads back and the new ignition coil is faulty. I have checked the pulser pick-up coils with a multimeter and the reading is within the spec's given by the Haynes manual (which couls also be wrong!!). Any advice would be gratefully recieved by a frustrated home mechanic