How to Shorten a Bike Chain
A bike chain is an essential part of a bicycle, and it needs to be the correct length to function correctly.
If your chain is too long, it will get caught on the frame or derailleur; if it’s too short, it could slip off the sprockets. In either case, you’ll need to shorten the chain.
- Put the bike in its lowest gear so that the chain is tight. this will make it easier to measure.
- Using a ruler or bike-specific measuring tool, measure the distance between the center of the crank bolt and the rear axle.
- Add 2 inches (5 cm) to your measurement. This is the minimum amount of chain you’ll need.
- If you’re unsure whether your chain is long enough, err on the side of caution and add an extra link or two. It’s better to have a slightly longer chain than one that’s too short!
- Use a chain breaker tool to remove links from the chain until it’s the correct length. Make sure to remove an equal number of links from both sides of the chain!
- Reattach the chain using the master link—if your chain didn’t come with one, you can use a quick link or a Shimano Pin Connector.
- Test the new chain length by pedaling forward and shifting through all gears. The chain should be snug but not too tight, and it shouldn’t fall off any of the sprockets.
- If necessary, adjust the tension on the rear derailleur using the barrel adjuster until the chain runs smoothly through all gears without falling off or skipping teeth.
Shortening a bike chain is a relatively simple process that anyone can do with a little time and patience.
With just a few tools and some know-how, you can have your bike running like new in no time!