Just completed a 2700 mile trip a few weeks ago on my '09 RKC--no issues, and ran like a top! On average, I got about 40-42 mpg.

 

If you don't have to deal with heavy traffic you're probably OK stock but if you ride in stop and go, you'll want to add a fueling device to keep the bike from heating up and going into parade mode. I went with a PCV, stage 1 A/C and an oil cooler, bike runs great.