Even with a class *4* receiver hitch, I wouldn't put a bike on the back of a vehicle like that. Now, if you had *3* of the receiver hitches and the carrier slipped into all of them at the same time, then I might trust the stability of it enough (for lighter bikes).@Rlc2009
What is total weight of bike with fluids, the carrier & straps combined?....
I'd say a no go though. Buy a little trailer to haul it with.
Also, with the Rubi and the fat spare, you will need a 6" or so, hitch extender so the bike clears the tire... this will compound the weight issue problem ..
It would take much channel iron to turn an old boat trailer into a bike trailer though. It would be low enough to the ground that you could even put a heavy bike on it, probably without even having to crank it up.