The Brits had this figured out many decades ago. The amount of flex in the knee at the top of the pedal stroke increases with longer cranks, thus causing an overall decrease in performance. There is a certain amount of flex in the knee that's considered ideal, and that's what people should be shooting for when choosing a crank length. I'm 5-10 and love 170's and 165's. Used to ride 175's for many years, and had a lot of pain, along with no performance increase that I could notice.




50 Years Ago: May 1970 in Bicycling! magazine