Half way down the page, looks like it can actually be done in situ: http://freewheelbike.com/articles/how-to...-pg475.htm
@Object 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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Half way down the page, looks like it can actually be done in situ:
http://freewheelbike.com/articles/how-to...-pg475.htm