How to Repair a Broken Bike Chain
Quick Road or Trail-Side Fix for a Broken Bike Chain
Getting stranded on the side of the road or miles down a trail is never fun. In fact, it is one of the main reason cyclists avoid riding alone. Learning some basic bike repair tips can help you feel more confident on solo rides and enable you to be the hero should a buddy have a bike issue.
A broken or bent chain on your bike is super common, so knowing how to remove sections of your chain and reinstall it is a necessary skill to have.
The following tips will help you repair a broken chain while out on a ride, but first, familiarize yourself with the parts of your chain so fixing it will be a cinch:
What You’ll Need
To fix a broken or bent chain, you will need to remove it from your bike AND remove the broken or bent links. To do that, you will need a chain breaker tool. In the video, we used the Park Tool Master Chain Tool, which is the best tool for the job. But if you are on the side of the road or trail, you will probably want something a little more compact. Most multi-tools will come with a chain breaker attachment, make sure yours has one before you leave the house!
In addition to being able to break the chain, it would also be handy to have an extra section of the chain you have on your bike to replace the broken or bent section. However, this isn’t totally necessary. Learn more in the step-by-step instructions below.
How to Repair a Broken or Bent Chain
If you notice your derailleur skipping and you are unable to stay in one gear while pedaling, you probably bent your chain. Although you might be able to ride home like this, it would be a little obnoxious and your chain could actually jump off the cassette entirely and break or bend your derailleur! If you have a set of pliers on hand, it is possible to bend the chain back and make it home. If you don’t have pliers, you’ll need to remove the bad section of chain. If your chain breaks completely, it usually snaps as you are putting effort into the pedal or if you apply force in another way, like landing a jump.
- Stop riding and flip your bike over. This is the easiest way to assess the damage, as you can easily pedal the bike forward to find the culprit of your issues.
- If the chain is bent and still attached to the bike, remove the chain using a chain breaker tool as close to the compromised part of the chain as possible. Push the pin all the way through, as you will toss this section of the chain.
- You do not have to remove the chain completely from the bike to fix a broken chain, but it can be a little cumbersome to kneel over the bike to fix it. If you remove the chain completely from the drivetrain, lay a piece of cloth you don’t really mind getting greasy on the ground to prevent your chain from getting super dirty.
- By bending the chain in your hands, you can figure out how much of the chain is damaged.
- Make sure you have a roller (see diagram) on the opposite end and the pin you are about to push through will leave you with two outer plates.
- Using your chain breaker tool, begin to push the pin through. Be careful to not push the pin all the way through the outer plate. You should be able to remove the damaged chain without letting the pin fall out completely.
- Thread the chain back through your derailleur and line up the pin on your tool with the pin in the chain. Slowly and carefully drive the pin back into the link to connect the chain. Check with the other links to make sure you pushed the pin in completely, but not too far through the link.
- Wiggle the chain back and forth with your hands to work out any stiffness in the newly installed link.
- You’re good to go!
TIP: You just removed a portion of your chain, so chances are the chain will not want to shift into the easiest gears on your bike (the biggest rings on the cassette). Be careful as you ride home to not shift into these extreme gears, or you might risk bending your derailleur. If for some reason you had to remove a large portion of your chain, you can by-pass the derailleur all together and make your bike into a single speed! Wrap your chain around the front chain ring and the desired cog in your cassette, trim the chain so it is tight and reattach. This method will also come in handy if you bend or break your derailleur.
The Deal with PowerLinks
But, what if you have a PowerLink, right? It is likely that your chain your bike came with has one of these quick attachments. A PowerLink allows you to remove your chain without a chain breaker and reattach your chain without fumbling with pressing a pin back into your chain link.
If you have a bent portion of chain and need to remove it from your bike, you can remove it with the PowerLink. However the bent portion is probably not located right at the PowerLink, so you will still need a chain breaker tool. Also, PowerLinks (especially on newer 11 or 12-speed drivetrains) are often difficult to remove without a set of needle nose pliers or special quick link pliers, like the ones below.
It is a good idea to bring a PowerLink with you in your pack or emergency kit because it is easier to reattach your chain with. But keep in mind that all chains require different kinds of PowerLinks, so make sure you have the right one.
When you reattach your chain with a PowerLink, there is a neat trick to use: Connect the chain with the PowerLink and pull the chain on either side to work the link’s pins into the holes. It is likely that the pins will not lock completely just by pulling. So, squeeze your rear break and press down on the front pedal. This pressure should pop the link into place!