I made my own rack out of square tubing. I mounted 2 square tubes under my front bumper, each half of the rack slides into the tubes with a pin. The bikes hang upside down by the wheels and I bungy cord tie them to the rack and my mirror posts. I have cheap bikes. I'd be upset if stolen but not a great financial loss. They do get wet and have a bit of rust, but I oil them up from time to time. The worse they look the less likely to be stolen.
Been thinking about making a similar rack. Looking forward to
looking at your idea.
I have the same attitude about the bikes, buy cheap ones and don't worry about them.
If I ever need a really good one I will just head up to the Carolina's...
Scott, your my hero...