I have a 2008 RKC, You can install slip-ons w/o any problems with running too lean. The bike will compensate for it. If you change to a hi-flow intake, w/o a re-map, then you will definitely have issues. Call around to other dealers (indy or HD) that are familiar with the newer bikes, they will tell you this.
Good Luck...

 

After much debate, I went ahead and had dealer do install on Sat for Vance and Hines Basic Slipons w/ no other mods to bike. Bike runs perfectly and sounds better than expected. I wish I would have done this sooner. Bike sounds like it should now. I will eventually do the stage 1 and download or pcV. Until then all is good! Enjoy the ride.