aim for 65 - 70 GI use this http://www.sheldonbrown.com/gears/ to work out g.i
@TheBrick(Tommy) 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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aim for 65 - 70 GI use this http://www.sheldonbrown.com/gears/ to work out g.i