One of the most common trail-side mechanical problems for a bike is a broken chain. While it could be the end of an otherwise great ride, with a bit of preparation, you can quickly fix the chain and get your bike back on the road.
Try backing off your effort (but still pedaling) when shifting between chainrings. Another way to keep the chain from coming off the inside of the chainset is to use a chain catcher. Chains break for many reasons, but the most common is wear. For example, if a chain has been ridden for 2500 miles, it will actually stretch out.
A frequently used chain will be longer from link to link than a new chain. Because the chain has been stretched, the metal fatigues are more susceptible to failure.
To learn more about why chains snap and how to fix and prevent them, read the article below!
How Often Do Bike Chains Break?
Most mechanics agree that you should replace your chain about every 2,000 to 3,000 miles, depending on your riding style. Many Tour De France riders wear out two or even three chains on their primary bike over the course of the three-week race.
What Happens If My Bike Chain Breaks?
A broken bicycle chain will render your bike useless but can be repaired on the road, at least sufficiently enough for you to ride home. You will need a bicycle chain tool that comes as part of most multi-tools and a spare quick link.
Reasons Why Chains Break
Here are some common reasons your chains may break.
Although many reasons result in your bike’s chain breaking, the simplest is wear. The chain is susceptible to wearing out once it reaches between 2000-2500 miles or more. The links will stretch out, contributing to the eventual breaking. As the chain wears, the chainrings and cassette (gears in the rear) will also wear out. Combine all those factors, mix in one bad shift, and you have the perfect recipe for a broken chain.
Therefore, having your chain checked by your local bike shop at least once a year is a good idea.
Like anything else on your bike, chains can be damaged if they get hit hard enough. While not as common, chains can break if struck by a rock or other objects. Impact damage to chains can be more challenging to repair than if the chain breaks due to wear.
The reason is, wear will typically only break one chain link, while impact can damage many.
Can A Broken Chain Be Fixed?
We’ll guide you through the process of fixing a broken chain below:
To start, you need to find and remove the broken link. How much of the broken chain you remove depends on how you fix it. Usually, you need to remove a complete link (one set of outer plates, inner plates, rollers, and rivets).
To repair, replace or adjust the length of your chain, you need to purchase a chain tool. A chain tool is a device that pushes the rivets into and out of a chain. Generally speaking, most bicycle multi-tools will have chain tools, but you can also buy them individually.
Here’s a helpful video on fixing a bike’s chain you can watch as you read ahead:
Removing A Broken Chain Link
For older chains, you can remove the broken link and mend the chain back together one link short. Keep in mind the chain length is very specific for the drivetrain to function.
If you shorten the chain, you will lose the ability to shift safely into the largest cogs. Therefore, have the chain properly sized and repaired at your local shop once you get home.
You will need to put the chain back together once the broken link is removed. Start by pushing the two link ends together and placing them in the chain tool. Force the rivet back into place with the chain tool.
Install A Quick Link
Quick links come in many different sizes depending on the number of speeds your bike has. From the 8-12 speeds, all chains will use different quick links that are not cross-compatible.
If only the outer plates are broken, you can cut them out, install the quick link, and ride off as if nothing happened. If an inner plates break, you must cut 1-1/2 links out of the chain before installing the quick link.
Install A Chain Pin
Installing a chain pin is necessary for all Shimano brand chains. Like quick links, they are speed-specific (i.e.. 8,9,10 speed, etc.) and not cross-compatible. To install a chain pin, remove the offending link and the rivet altogether.
Then, put the two chain ends together (held in place by the chain pin) and use the chain tool to press the pin into place. Once the chain is installed, break off the portion of the pin protruding from the back of the chain.
Breaking a chain is rarely an isolated incident, and more frequently, it is the sign of a larger issue. If you do break a chain on the trail, be sure to get your bike to a professional for an inspection.
Additionally, if you need to replace the chain, be prepared to replace the cassette and possibly chainrings as well. Considering all the parts of your drivetrain wear together, attempting to introduce a new part into that group might not function well.
We hope this information is helpful, both for situations when you are out riding and when you need to bring your bike in for servicing.
Bike Chains are often broken, and there are various reasons for it, such as the wear and tear the chain goes through. However, there can be other reasons, like the impact of stones from the road on the chain.
But it’s not hard to repair the chain if it keeps snapping, and you can do it yourself!
I always had a thing for cycling sports and love almost anything that involves bikes and boards. I work part-time as a designer in the tech industry and work on my blogs whenever I can.