I'm new to fitness cycling and commuting. I was using an old mountain bike with road tires for riding but on kept it between 2-3 gears. I recently got me a Trek 7200fx and now I can ride comfortably between 7-9 gears. I'm just wondering how many gears some of you go between on your rides, both fitness and commute? My fitness ride is on a paved bike trail with one short but steep uphill and another short but steep downhill, otherwise pretty flat.