Brokenchain

Bike chains don’t often break but it’s worth carrying a quick link or a multi-tool that includes a chain tool. Unthread the broken chain from your bike. If you have a quick link, just remove the damaged chain link, using the chain tool to push the pin through the outer and inner plates. Rest the front of the chain on the bottom bracket shell and route the rear end through the front derailleur, across the cassette and through the rear derailleur. Draw the two ends of the chain together below the chainstay and join them using the quick link. Replace the chain onto the chainring.

If you don’t have a quick link, you need to remove two links from the chain, including the broken one. Use the chain tool to push the pin through the chosen link, only as far as the furthest outer plate as you need to reinsert it. Route the chain across the bike as previously described, then join the ends using the chain tool to push the pin back through the plates. The new join is likely to be stiff, so flex it with your hands until it moves freely. Return the chain to the chainring, and avoid shifting to the larger cogs to prevent putting too much tension on the newly shortened chain.