Depending on the hill, I've noticed I go anywhere from 4 to 10 mph, sometimes as low as 3. It sucks when you're trying to chug up a hill at 4 mph though and people go speeding past you...had that experience this past weekend on my century ride, but I had to remind myself that a lot of those guys were racers and were in much different condition than I. I mean, the Tour de France racers were going up some of those hills at 25 mph - no way are we going to be doing that anytime soon! Like everyone else said, as long as you get get up the hill you're good!