The bike industry is phasing out 650c rims/tires. racers were tired of buying fancy wheels for TT's and Tris and having to buy another fancy set for road racing. there is a reason that Trek's CF TT bike used to have 650's and now has 700's. That being said, in my garage right now, I have bikes with 20's 26's 650's 700's 27's and old schwinn standard. I love planned obselesence.