I graduated from a four year apprentice program as a welder at the former Philadelphia Naval Shipyard back in 1984 and then became a pipe welder at PNSY. I write this not to toot my own horn but to humbly say that I have not seen one bumper on any RV that l would put any trust or faith in attaching anything to it. Every bumper I have seen has not been welded but more or less just had some molten metal thrown on it which was called a weld. Please to the OP, reconsider and do not bolt a bike rack to the bumper, the cars behind you do not need your bicycles bouncing onto their windshield.