How to Repair a Broken Bike Chain

There is nothing more frustrating than a broken bike chain, especially when you’re already on a ride or preparing to meet friends in half an hour for a long cruise. Fortunately, however, you can fix a broken chain rather easily if you have the correct tool and understand how the chain works to keep your bike in motion. The handiest tool you’ll ever purchase is called the chain break tool, and is available at most bike shops and hardware stores for less than $15.

When you first discover that you’ve got a broken bike chain, get off your bike immediately (if you’re riding) and examine whatever damage may be evident. For example, chains can easily become jammed between the frame and sprockets, in which case you’ll have to untangle the mess. Get out your chain break tool and prepare to get your fingers rather dirty.

Step 1

Stretch the bike chain out with the broken link in the center. Using your chain tool, push the faulty pin out, making sure to push the pin away from your body. You can then set your chain tool down on the ground while separating the two links. It should make a soft snapping sound, which is fine.

Step 2

Turn the chain so that the pin is now pointing toward your body, making sure you don’t tangle the bike chain or cause any twisted links in other parts of the chain. On some bikes, especially those with plenty of flexion, you can usually remove a link or two without causing any damage to the derailleur. If this is possible, you can simply reattach the non-broken link, or you can add a fresh one from a kit or from a previously discarded chain.

Make sure you have adequate light shining on your hands so that you can see what you’re doing, and snap the unbroken links back together with the pin in the center. Again, it will make a small clicking or snapping sound, which is perfectly normal.

Step 3

Next, use the chain tool to push the pin back into the two links. You’ll need to make sure that the links are straight and not damaged in any way. If they are, you can use a spare link that you’ve removed from a different chain, as long as the two are compatible. Also, make sure you don’t twist the chain tool too hard, or you might wind up damaging the pin, which will force you to purchase a new bike chain.

Step 4

Finally, you’ll want to move the chain in all different directions to ensure that the connections are solid. You can use your chain tool to readjust the pin if necessary, especially if it doesn’t look even from both sides of the links. You can pull at the chain, and it shouldn’t break or jam if you’ve done this correctly.