LFGSS
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
I read somwhere a bike Mfgr in England calculated 149 MM is the optimum crank length for power vs efficiency, which matches up with that graph. Back in the old days (70s-80s, when East Germany dominated the match sprints) it appeared those guys were using quite short cranks. I used 165s on our track in Minneapolis. The slowest speed they told us we could go was 15 mph before you clip a pedal. If you clip a pedal, that raises the back wheel and you go down. With my high BB and 165s I never came close. As a match sprinter, you avoid slow speeds in the corners anyways and try to use the straighaways to play chess with your oponent. Our track was 43 degrees in the corners and 11 on the straights. Some 250 M tracks are 45 and I think the shorter tracks even steeper. I'm interested, however, in what kind of crank arm lengths sprinters are using these days because the 200 M TT WR has droped to under 9.2 or so. That's a huge improvemement that can't be explained by high tech bikes. I'm thinking the guys that can put out 2500 watts on their bikes are figuring out ways to leverage that power more efficiently (pun intended). I don't think they are trying to spin 160+ rpms anymore like we tried to do back in the day. I just wonder what kind of crank arms they are using to harness that big power.