It depends on how often you ride. I ride 4 to 6 hours per week on average for about 8 to 9 months out of the year and I think I had to change my Terry Butterfly after 2 years use. I also think that I left it too long. By the time I figured out why my arms felt so tired after my rides, it was pretty broken down. It's possible that I have more problems with breakdown because I'm in the aero position a lot.