To fix a bicycle chain, remove the broken link, and then assemble the chain again. Use a replacement pin, or trim the chain with an outer plate with a pin on one end and a roller on the other, and snap the ends together.
- Take out the broken link
Get the chain tool out of your seat bag, and take out the broken link. Take care while removing the link to avoid bending the other pins and rollers.
- Insert a new link into the chain
Get a replacement link from your seat bag, and insert it into your chain. Trim your chain to give an outer plate with a pin on one end to connect with a roller on the other. Push these ends together and slide the pin through securely.
- Use alternate connection methods if necessary
Look for a piece of string or wire on the side of the road if inserting the pin into the roller does not work, and use this makeshift solution to hold the chain together while you ride home. Make sure that you pedal with care. Watch your shifting even if the pin-and-roller solution works because you have shortened the chain and using the combination of a large cog and large chain ring puts the chain at risk.