Smaller tubes generally work fine in larger tyres within a couple of sizes. I've run 25 in 32s fine before.
@atk 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.
Smaller tubes generally work fine in larger tyres within a couple of sizes. I've run 25 in 32s fine before.