generally 531c was used for racing bikes, while something like 531st would be used for touring. doesn't necessarily mean you couldn't use your existing frame though...
@pppp started
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.
generally 531c was used for racing bikes, while something like 531st would be used for touring.
doesn't necessarily mean you couldn't use your existing frame though...