Originally Posted by smashndash

Actually the 5800 caliper has the SLR-EV design.

The pivot points are symmetrical. I have 2 105 R7000 calipers, and you should have absolutely no problem getting these things centered and hitting the rim at the same time. I agree, though, that typical dual pivot designs are absolute garbage.

Please upload a video clip to youtube or something. This is probably like a 2-minute diagnosis that we're agonizing over.

So there are a couple of things that can cause your problem, and a loose mounting bolt, believe it or not, isn't one of them. You could have "too short" housing. This could also just mean you need to pull some slack into the housing near the caliper because the housing has slipped into the frame. If that's not it, then make sure the brake shoes are at the same level on the arms. If they are... then this is a longshot, but try adjusting the small centering bolt. But my bet is that it's a housing issue.

EDIT: I can't believe I missed the second page. My bad. I think it didn't load on the desktop site with its newfangled autoloader. Great that it worked out, though.