When I was in Knoxville, TN last year (Don't know the actual height above sea level) I was still running the 118 mains w/5181 needles, bike was still rich, but not badly so, and not necessarily due to the elevation. Bike had good power and pull, and incredible gas mileage (50+) and that was going through the Dragon is 2nd gear screaming along. I would recommend the 115's, but also take a look at your main air jets too, those are actually the easiest to access. And don't forget about maybe doing a high throttle plug check, just be careful doing it. That's still the best way of checking your burn.
