http://www.eehouse.org/fixin/stretch.php thats all they say but it seems that its just for calculating the magic gear...
@marcoisapolo started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
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http://www.eehouse.org/fixin/stretch.php
thats all they say but it seems that its just for calculating the magic gear...