5.3 pounds is too heavy for it to be made from 853 if you're talking about just the frame, no fork. I have a 29er mountain bike frame made from Reynolds 853, it has disc brake mounts welded on, has extremely long chainstays to accomodate fat 29er mountain bike tires, and has gusseting welded on to the downtube/headtube junction to add strength. The frame weighs well under five pounds. And a friend of mine has a nice road frame made from 853, the frame weighs about 3.5 pounds.