Re: 2 days ago, only 1 cylinder firing, yesterday BOTH, today just 1 again.

Hi,  I identified the problem my virago 86 700 was having. I narrowed it down to a failed float. The failed float, altough it floats, weighed 2 grams more than the functioning one. I figured out that it was the floats by swapping them. When i swapped them, the other cylinder started working, and the previously failing one was firing.  Maybe you should try that sawp.
My failing cylinder, like yours, also had fuel leaking out of the exhaust. .. a lot.
I havent posted anything as (solved) yet though because i am still waiting for the new float. I was able to find one at boats.net. It's taking two weeks to get here.
It sounds like your coils are probably alright. Especially if they are both the same exact ohms. Maybe you should try testing for spark by removing the plug, reconnecting it, and holding reak close to the engine. (make sure chokes not on, and put a rag over spark plug hole, or you can get sprayed with gas in the face like i did.)
If your sparks not strong enough looking, I think some people put some kind of Accel Harley coils in their bikes to fix that sometimes.. i cant remember the details, but i read about it on VIrago Tech Forum once. you should check that forum out.. they're good.  Goodluck! let me know how it goes.