I ride a single speed because it is fun. I only have one bicycle, a 20 year old trek 720 road bike. About 4 years ago I was forced to stay in one gear because of worn cogs on the rear and a bent rear derailleur. When I would go into bicyle shops looking for a derailleur (friction shifting) and a 6 speed maillard heliomatic freewheel I felt like a dinasaur. They explained to me the need for more gears and something called index shifting plus the parting of some well earned cash. All the while I was enjoying riding my bicycle as much as I ever had. So a couple of years ago I converted the multi speed bicycle to a single speed and havent regretted it one time.