I have 03 heritahe springer and have been fighting my seat. On long runs (short ok) I get bad numb butt after only 120 miles. This gets worst as the day goes on, long rides of 600 miles or so. Tried jel and air pads, nada. Is it possible it might be my handle bars or placement of foot pegs or all. I was told because the seat rides on the frame, live with it. Not!! Rebuild seat? Could really use some info.