Take the coil off and carefully inspect it top and bottom for hairline cracks.
The OP has a Vulcan. it has one coil pack. Not 6 COPs like the duratec.Get ready to replace the coil. I guarantee that within 6 months you'll need to have it replaced, probably sooner.
Since you have the time, I forget if the #1 Coil is one of the easy ones to get to. If it is, you should buy yourself that part now and just do it...if not, you may want to consider getting all 6 and either paying someone to do all of them for you, or do them yourself.