Most 29ers should have long chainstays. My (Redline Monocog) 29er has 44.5 cm chainstays. With an IGH, I have no problem averaging 12-15 mph (and higher), even with my flat(-ish) bar well above saddle height. Mine is configured for street use, and I use it for everything, commuting, grocery & laundry runs, and fully loaded touring.