I found this calculator, which some might find useful :)
https://docs.zoho.com/sheet/published.do?rid=p2rrnf78b800f51254a4981208481abdf96a7&mode=embed#
@MechaMorgan 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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I found this calculator, which some might find useful :)
https://docs.zoho.com/sheet/published.do?rid=p2rrnf78b800f51254a4981208481abdf96a7&mode=embed#