You need both if riding single speed. For safety, common sense and you can get fined if without. Plus single brake on a single speed looks really crappy.
@edmundro 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.
You need both if riding single speed. For safety, common sense and you can get fined if without. Plus single brake on a single speed looks really crappy.