But, also do your research on bike racks to use - there are almost none that are designed for RV use. You usually have to download the manuals for each make/model, and read the fine print, where it explicitly states that trailer/RV mounting voids warranties and/or even stronger language about possible failure of the rack itself.
Swagman is the most common one that does allow it, and they only have two of their many models that do not exempt RV's.
The greater distance from rear wheels to the bikes on an RV makes for a huge "force multiplier", that greatly amplifies any bump in the road. Hence the twisted off bumpers for bumper mounted bikes.