I seem to have endless problems with batteries myself. Got a couple years out of the factory battery, then a couple of Sam's, a Yuasa, another Sams, and last July got some new "Gel" battery from O'Reilly's. All of the replacements lasted a year or so, except the last one, which died sometime in the six weeks while I was sick with pneumonia right after Thanksgiving. I don't mind the battery running down because I forgot to put the tender on it, but all of those replacement batteries, when I took them in to be charged, had a "dead cell" in them. Is this just the way modern batteries are, or could there be a short or ground problem in the bike that's killing them during idle periods? Seems like I ought to get more than a year out of them... (Sorry if this is a thread hijack, but the question seems relevant....)After all the other electrical problems you have had on this bike, it is hard to say for sure. I guess I'd have to start all over at square one again. My gut feeling is that the original problem your bike had still exists and hasn't been repaired, and due to the strange behavior of it, my first suspicion is you have a bad ground somewhere on the bike, or in one of the junction connectors in the wire harness.