The guy who invented the first wheel was an idiot -
the guy who invented the second one... he was the genius!
http://theringfinders.com/blog/Larry.Royal/
I had the same problem, especially the "hunching down" feeling. I added a backrest and the pain went away .....
Just my 2 cents ...
I had the same problem and brought the bars up and back (Kuryakyn kit) but then the pain moved to my tail bone. I moved it back to stock and then moved them up 3/4 inch with just the Kury wedges and it's been fine ever since. Much better than before in the stock location. I want to add a backrest soon though to help keep me from slouching.