I recently bought a Thule 917XTR T2 Hitch Bike Rack for a carbon bike because it clamps to the wheels without touching the frame. My bike frame has a custom paint job which is pretty cool. I am just trying to protect it from rubbing against clamps or straps. This Thule rack just touches the wheels. The frame will eventually get dinged from riding but for now I am trying to keep it perfect.
One of the side benefits is that this rack is very fast to load. It takes like 15 sec to put the bike on and strap it in if the rack is already on the vehicle.
Mounting the rack to the vehicle is like any other rack. You have to get it in the hitch receiver and run down the threaded retaining pin on the receiver. I do that in about 2 seconds or so with an air wrench. Your times may vary.