I have now owned my 2004 12R for a full year. The two previous owners have insured that I became at one with my profanity. Electrical issues everywhere, front to rear. Right now the current issue goes like this: I have (for the 5th time) *fixed* my tail light. The light will intermittently go out. The brake light will still function so I don't worry too much when stopped at a light. But the running light is very important for visibility at night. So what do I do? I take the assembly off, check the wires and connections, check the bulb, test everything, and I get a 50/50 chance it works.

At this point I assumed my rear light assembly was bonked, but I had a spare laying around from another tail section I purchased earlier. Still the same issues. So off goes the rear body work to chase some wires. Everything looks kosher, and I cannot figure out where my issue is. Everything tells me it has to be rear assembly, maybe something as simple as the connections touching the bulb, but nothing I do fixes the issue permanently. OK.. Right now I have the brake light and running light working. I will go for a ride later to see if it works, or fails again.

Another interesting electrical issue that I have bandaged, though not solved goes a little like this. Low beam headlight assembly keeps melting. I mean the thing goes full on nuclear. So I check the power of the bulbs, everything checks out. I make sure I am using the correct 55w H3 bulb. Have some friends and my father check everything with me to make sure I am not going insane. After 10-20 hours of riding the assembly is fried. I go through like 3 of these things, and they aren't cheap. WHY IS THE LOW BEAM SO HOT? I run during the day with the high beam always on, and it has the same bulb as the low, yet the high is just fine. So I wise up and decide to get a lower wattage bulb for the low beam. I go with a 35w bulb. But just for giggles, I grab my infrared thermometer and read the temps. The 55w high beam is running at 114 degrees. The 35w low beam is at staggering 145 degrees. Both have the correct power running to them. I don't even want to know how hot the 55w bulb was burning.

I now have a LED bulb in the low assembly, which is crap at night. I cannot scratch my head enough over these issues. I think I need an entire new wiring harness.
Great bike, I love my Buell. But good lord did I get a difficult one.