I also am trying to overcome fear of going fast down-hill. I was fine until about a year ago when I had a major blow-out of my front tire. I was only going about 30 mph but found myself scrambling to unclip from the pedals and get stopped as the front tire flopped from side to side off of the rim. No fun! Now I am apprehensive but working on it. I tell myself it is not likely to happen again, but by elbows begin to tremble involuntarily. If I was 25 I wouldn't think twice about a 45mph desent, but at 44 it takes longer to heal.