anything under 1.5 hours I just drink powerade zero. Above an hour and a half I bring along nutrition also. I have found that I can keep a good pace with little nutrition out to 2.5-3 hours. My main goal is to loose weight. I started tracking calories and realized on a 30 mile ride (~1.5 hours) I was consuming 800+ calories eating 2 whole wheat eng muffins for breakfast, a couple of gels, and gatorade g2. I was like **** I am using all the calories I burn fueling for the ride. Since I have cut down to 1 eng muff w/ straw pres and powerade zero and the results have been good. my speed is improving. it is a case by case basis and to some degree depends on what your goals are.