I know the Voltage Regulator issue has spawned into many threads, but I just wanted to tell my story:

I was in Sturgis for the rally. On Tuesday, we were heading out towards Needles Highway when it happened. After sitting in traffic in downtown Sturgis, I saw my voltage drop and check engine/battery lights come on. Thanks to visiting this forum often, I knew immediately what had happened. I believe the heat that day was the straw that broke that camel's back. I was able to "limp" the bike back to the campground and then get a trailer to haul it over to Rapid City at Black Hills H-D. Once I got it there, all I had to say was two words - "Voltage Regulator". The gentleman pointed to the right side of all the bikes waiting for service and said "The Voltage Regulator line is over there." It was nice not to have to explain my issues or symptoms. Three hours later, I had my bike back and was able to ride, losing only that day's worth of riding. It could have been much worse.