We have a 2015 Shasta Flyte 225RS travel trailer. It has a spare tire on the back. I'm looking for a rear bike rack that can accommodate 4 bikes on the rear bumper. Is there such a thing? It seems like the ones I have seen, won't actually take 4 bikes because it looks like the spare tire will be in the way. I'm also trying to find on the Shasta flyte what the bumper is "rated" for weight capacity...can't find it. Pretty much found all the other stats for the trailer!!