The majority of us do not give it much thought if the bike chain comes off because it happens occasionally. The chain slipping off the bike is a nightmare. If you have to stop every few minutes to put the chain back on, an outdoor journey is not something you can enjoy. To identify and address the issue, it is preferable to become familiar with the bike chain's operating principles.

How Does the Bike Chain Works?

A chainring, one or more derailleurs, a cassette, and two crank pedals are used to power the bicycle chain. Your feet must be on the pedals in order to push the crank to turn in order to drive the bike ahead. The bike chain will move in tandem with the chain as it moves. The chain's holes and the chainring's metal teeth fit together flawlessly.The chain is forced to travel from the upper side of the chainring to the lower side by the rotation of the chainring. The bicycle chain's force is transferred to the wheel's cassette. The bike chain enters from the bottom and leaves from the top to deliver power. The back wheel is able to rotate thanks to this constant action. To switch the chain between the cassette's various rings, a derailleur is located on the side of the rear wheel.

Top Potential Causes of a Falling Bike Chain

You must become familiar with the various factors that contribute to the bike chain's malfunction in order to comprehend the causes. Numerous factors could be at play in the bike chain problems. The problem's most common potential causes have been compiled by us. Once you are aware of these problems, troubleshooting will be simple.

Clogged-Up Chain With Dirty Links

One of the minor issues for the chain coming off is a filthy chain. The chain picks up some dirt when traveling on a gravel road. The chainrings may become clogged by these dirt and stone fragments. The falling-off problems in the chain might be brought about by just a few clogged openings. They prevent the chainring teeth from fitting in when the clogged hole appears on it. The chain will be forced to come off the chainring or cassette due to these slight alignment difficulties.

Inappropriate Chain Length

When installing it, the technician will modify the chain length to fit it exactly. Stretching forces increasingly control the chain as time goes on. The chain length can be impacted. A stretched chain won't travel directly from the chainring to the cassette. The approach will be curved. This problem is easily recognized because the chain forms a U-shape as it travels from the lower side of the chainring to the cassette.

Uneven Chainring

The uneven chainring may be the cause of your chain coming off after the bike has fallen. The bike chain will vibrate sideways if the chainring does not revolve in a straight path. When you are paddling the cycle, you might not detect this vibration. To turn the pedal with your hand, you must get off the bicycle. The vibration in the chain will let you know whether the chainring is uneven.

Damage to cassette

Finding problems with the chainring is easier than finding damage to the cassette. To identify the problematic ring, you must examine each of the cassette's rings. The gears can be changed to do this. The number of the gears that are causing the chain to come off must be noted. Following the bike crash, all of the rings may occasionally not be in proper alignment. Based on this diagnostic, you can choose whether you need to repair or replace the cassette.

Misaligned derailleurs

Derailleurs problems can occur if you ride an ancient bicycle. The issue is particularly noticeable on bikes with multiple gears and shifters. By using the shifter on the bike handle, you may change the gear. This component may be at fault if the chain comes off when shifting gears. You can change gears several times to determine where the chain comes off. This method can be used to identify issues with the cassette and derailleurs.

Wrong Size of Chain

It can be surprising to know that your bike has the wrong chain size. Length is not the only parameter you have to consider when choosing the bike chain. You need to choose the accurate width also. If you do not install the correct chain, it may come off often. You may not notice the problem when the chain is new as it will handle the chainring and the cassette at the start. As the chain gets a little old, the falling-off issue gets worse. You can check the internet to find out about the chain size for your bike. It is better to consult an expert to find an accurate chain size.

Rusted Chain

After being used for a while, the chain holes may develop unevenness. When you look attentively, you can see the bike chain's wear indicators. You must inspect the chain and the interior of the holes for scratches. You can label a specific chain link if it has any scratches. You'll know what to look for if the chain breaks off from the same component.

How to Fix A Bike Chain That Keeps Falling Off

You ought to understand the reasons behind and a proper diagnosis for the chain falling off after reading the causes. If you correctly diagnose the problem, it may be resolved. Some of the methods can be used to solve the problem. The fix may be as straightforward as cleaning the chain or as complex as replacing numerous drivetrain components. We'll concentrate on things you can accomplish on your own. If things don't work out, you can talk to a qualified technician.

Chain Cleaning

Simple maintenance can prevent the chain from slipping off. For this, you can get a brush and a little screwdriver. Start by using a brush to clean the chain. Once it has been cleaned, use the thin screwdriver to remove the little stones from the chain holes. Prior to taking any further action, it is preferable to clean the chain. Find out more information about cleaning the e-bike chain here.

Rear Wheel Adjustment

You can adjust the bike chain if it has slightly stretched by shifting the location of the back wheel. The rear wheel's bolt can be loosened and pulled backward. The rear wheel can be fixed in place by tightening the bold after the chain is secure. You can fix the problem without changing the chain with its assistance.

Correct the Chainring Wheel Uneven Surface

Take a wrench to adjust the chainring's uneven surface. You should search for misaligned teeth. The wrench can be used to adjust their alignment. You can also straighten a little bent in the chainring by using a larger wrench. Before attempting to modify the chainring, it is preferable to remove it. It will safeguard other components from harm.

Correct Cassette Alignment

The wrench can be used to adjust the cassette alignment as well. For the smaller gears, you can also use pliers. The diagnosis and resolution of the problem will require further time. It is preferable to seek out expert assistance if you are having problems with the cassette. They have equipment to verify alignment.

Derailleurs Correction Adjustment

There are two methods for adjusting the derailleurs. Find the limit screw that keeps the chain from coming undone. To correct the chain delivery to the cassette and chainring, you must turn this screw. The metal component that connects the derailleurs to the bicycle frame can also be adjusted. The more recent models of bikes also require that adjustment.

Chain Replacement for Bikes

You must replace the chain if it is worn and other attempts to stop the chain from slipping off have failed. Finding a specialist with considerable cycling knowledge is crucial. He will assist you in locating a chain with the proper width and length. He will correctly adjust the chain to prevent any further issues. If you are an excellent biker, you can complete it alone as well. You may get a lot of information regarding chain replacement in online sources.


The drivetrain system on a bicycle depends on the chain. Without the chain, the bike will not function. The chain slipping off the bike can be caused by a problem with certain of its components. With the help of the directions in this article, you can identify the problem. Some issues are better resolved on your own. The best course of action is to seek professional assistance if there is something you do not understand. To assist you in resolving this problem, search online for articles and video lessons.