works shocks will build what you need for your load and riding style. i've got their shocks/fork springs on my 07 streetbob and they're a big improvement over stock.

 

I used to be 298 pounds and I had the stock shocks set on the middle setting and never bottomed out. The ride was better than the shorter 11 inch Progressive shocks I have now too.
Something must be wrong with your stock shocks or you have some extremely bad roads.