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Bike Chain Slipping When Pedaling Hard – Causes & Solutions

Written by Gary Johnson / Fact checked by Henry Speciale

bike chain slipping when pedaling hard

A long stretch of road or a steep climb can be overcome by an appropriate level of effort when riding a bicycle. However, things can get dangerous with our bike chain slipping when pedaling hard. What causes this?

The bike chain coming off can result from a worn-out chain, damaged gears, and a few other causes. This is a sign that work needs to be done on the cycle soon.

Keep reading to learn the important details.

Common Causes of Bike Chain Slipping During Hard Pedaling

Bicycles have developed much over the years, but we still experience mechanical problems more often than we’d like. One of these is when the bike chain keeps falling off in some situations, such as when we are pedaling hard or in high gear. 

Such an issue is fixable, and here are some potential causes: 

  1. Dirty components
  2. Chain condition
  3. Damaged cassette
  4. Improper chain installation
  5. Misaligned bicycle derailleur

Some of these are easy to spot while some may need to be attended to by a professional depending on the severity of the problem. Let’s take a closer look at each one.

How to Fix a Bike Chain That Slips During Hard Pedaling

1. Dirty components


A dirty cycle will encounter problems, with the bike chain dropping being one such issue. Mud, dirt, and grime will prevent the bicycle from working as intended, and leaving this will cause further damage in the long run.

However, it’s not just a dirty chain that can cause problems, as dirty gears and sprockets can also cause problems for bike operation. Mountain bike chain slipping due to this is especially common, as MTBs can get dirty quickly when used on trails and tracks.

How to fix:


A thorough cleaning is a good first step when experiencing any problem, not just the bike chain jumping. It can address simple problems and allow us to properly assess the different components and see if anything else needs to be given attention.

Disassemble the bicycle parts and be sure to clean each one thoroughly; use a degreaser to make things easier.

Once you’re done, apply grease to essential parts such as the chain. However, be careful not to use too much lubricant, as this can also cause the chain to slip.

2. Poor chain condition


When the bike chain falls off repeatedly, it makes sense to wonder about its condition. An old chain may be worn out, causing the problem. It may have stretched out from use leading to it dropping, and will need to be replaced.

How to fix:


First, we need to check the chain for its level of wear using a chain tool. Insert the chain tool’s teeth into the slots on the chain. The easier it is to slip them in, the more worn the chain is.

If the chain is worn out, you’ll need to remove it using a chain breaker tool. However, if you have quick links, it will be easier, and you can remove it with a pair of pliers. Look for links with elongated slots on them, and you can slide the link out to unhook them.

Don’t forget to lubricate the chain before finishing up.

3. Improper chain installation


Another possible cause of the bike chain skipping under load is if it was not properly installed.

Some bicycle part manufacturers have specific installation instructions, such as which side is on the outside or which direction the chain needs to move toward.

Making a mistake here can cause hiccups in the drivetrain and cause either skipping or falling off.

It’s also worth mentioning that installing the wrong type of chain will be a problem. Always ensure that you are using one that is compatible with your bicycle.

How to fix:


All you need to do is remove the chain and put it back properly. Follow the same steps in removing the chain, then check it for markers on which side goes where.

If you realize that the part you’re using is incompatible, replace it immediately.

4. Damaged gear or cassette


If the cassette or any of the gears is damaged or worn out, the chain will end up skipping teeth or even falling out. Chipped gear teeth will make it difficult for the chain to retain its grip causing the problem.

Even if the damage is only on front sprocket or seems minimal, this needs attention, especially when you have a very old or worn chai.

How to fix:


Replacement is the only real option, and it is best to do this right away. Continuing to use a bicycle with damaged gears is dangerous and can lead to worse damage than just the chain of the bike slipping gears.

Be sure to thoroughly read and follow the manufacturer’s manual for installation or get professional help to avoid damaging your newly-bought part.

5. Derailleur misalignment


The section at the bike rear cassette slipping could mean a problem with the rear derailleur’s alignment, which needs to be adjusted.

Both the front and rear derailleur may encounter issues caused by a strong impact from riding or even during reassembly after cleaning or a tuneup. The misalignment can put chain problems under pressure.

How to fix:


First, check to see if the derailleur is bent; if it is, you’ll need to straighten it into shape. You may also need to adjust the limit screws on the derailleur.

You would find two screws on each derailleur, usually labeled with H and L. If the chain drops inside, you’ll need to adjust the L screw; if it drops outside, it’s the H one.

Preventing Bike Chain From Slipping When Pedaling Hard

It is said that prevention is better than cure. With bicycles, it starts with ensuring regular cleaning and maintenance on our cycles. Mud and dirt bring a lot of problems, and keeping them off helps our cycles last longer and perform better.

There’s also an attachment that you can use called a chain catcher that can help prevent the bike chain popping off. Some derailleurs also have stabilizers that help prevent chain slips.


Now you know some of the most common causes of a bike chain slipping when pedaling hard. A bicycle has many parts, and knowing everything about keeping them all working well is very difficult. However, just learn what you can and you’ll find it useful at some point.

Have you experienced chain slips on bike caused by problems not mentioned in this article? Tell us about your experience in the comments section below so that everyone can learn more.

Always ride safely.

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