How to Change and Reattach a Bike Chain

When your bicycle chain gets old and stretched, it’s time for a change. Learn how to switch out your bike chain with these Pro Tips.

Time and use can take their toll on your bike’s chain. The more you ride, the more stretched out and worn in it can get. And the more damaged it is, the more wear it can put on the other components of your bike. Thankfully, with a few simple tools and these Pro Tips from GT Pro Rider Rachel Strait, changing your chain is something you can do from the comfort of your own garage.


To make room for your new bike chain, you first have to get rid of the old one.

“The first thing you’re going to want to do is make sure that you’re all the way in the lowest rear cog that you can be in,” Strait says.

Once you’re downshifted, release the tension holding your chain in place. To do this, you can push the derailleur back, giving your chain some slack.

Many chains come with a master link that can be used to release it from the cogs without having to break a link. You’ll need a pair of master link pliers for this. Put the pliers around the master link and squeeze until it pops open. From there, the chain should slide right out of your bike’s cogs.


When you’re attaching a new chain to your bike, you need to make sure it’s the right size. The size of your chain depends on your bike and the number of sprockets on your rear cassette — the set of cogs on your back wheel. You should be able to use your old chain as a guide for which new chain to purchase.

Once you have your new chain in hand, it’s time to measure it and cut it to fit your bike. Strait has a simple trick for finding the perfect length.

“What I do is I hang on to the chain that I just removed from the bike,” she says. “Even though it is stretched out from use, you can measure it, line it up against the new chain so you know exactly where to cut it.”

When you determine the length you need, you can use a chain breaker to remove the excess chain. Line it up with the last link you’ll need and press the chain breaker until you hear a pop. That’s the sound of the chain link’s pin being pushed through, which splits the chain into what you need and what you don’t.


The final step in changing your bike chain is to put the new one on. Thread your length of chain back over the lowest cog and through your bike’s derailleur. Connect your master link to both ends of the chain and pull tight until you feel in snap into place.

“Make sure your chain is all the way on, get some tension in there,” Strait says. “Then we’re going to pedal forward and voila!”

With your new chain in place, you can get back on the road or trail without the worry of a sluggish, stretched-out chain dragging you down.

Have more questions about your bike chain? For help with tune-ups, installations, adjustments and repairs, visit our bike service PROS at your local DICK’S Sporting Goods.