Why Is My Bike Chain Skipping Under Load? (9 Reasons)

The chain on a bike is an important part of its drivetrain, and it is responsible for transferring power from the pedals to the wheels. A skipping chain can be a frustrating problem that can occur for a number of reasons.

One common reason for a skipping chain is a loose chain. A loose chain can cause the chain to slip off the gears, which will cause the chain to skip. The chain can also become loose if the chainring bolts are not tight enough. 

Another common reason for a skipping chain is a bent chain link. A bent chain link can cause the chain to bind up, and this can cause the chain to skip.

In this article, you will know the reasons why bike chains skip underload and how to fix them.

Why Is My Bike Chain Skipping Under Load? (9 Reasons)

Bike chains skipping under load is a common problem that can be caused by several different factors. The most common reasons are listed below.

Here are 9 reasons why is my bike chain skipping under load:

  1. Cable tension
  2. Damaged drivetrain
  3. Gear indexing issues
  4. Mismatched drivetrain
  5. When something is wrong with the bushing/bushing interface
  6. Worn cassette
  7. A worn or damaged chain
  8. Worn or damaged sprockets
  9. Dirty chain

1- Cable tension

When it comes to diagnosing why a bike chain is skipping under load, there are a few potential causes. One of those potential causes is cable tension.

Cable tension is the amount of force that is being applied to the cable that runs from the shifter to the derailleur. If the cable is too loose, then the chain will have too much play and will skip. If the cable is too tight, then the derailleur won’t be able to move the chain properly and will also cause skipping.

How to fix it?

To check the tension of the cable, you’ll need a tensiometer. You can find these at most bike shops. Once you have a tensiometer, simply attach it to the cable and see what the reading is.

If the reading is too low, then you’ll need to adjust the barrel adjuster on the shifter. If the reading is too high, then you’ll need to loosen the cable by undoing the clamp at the derailleur.

Once you’ve adjusted the tension of the cable, you should test ride the bike to see if the skipping has stopped. If it hasn’t, then there are a few other potential causes that you can check.

2- Damaged drivetrain

If your bike chain is skipping under load, it is likely because the drivetrain is damaged. The drivetrain is the system of parts that transfers power from the pedals to the wheels. It includes the chain, chainrings, cogs, and bearings. When any of these parts are damaged, the drivetrain will not work properly and the chain will skip.

How to fix it?

If you suspect that your drivetrain is damaged, take it to a bike shop for inspection. The bike shop will be able to tell you if any of the parts need to be replaced. In most cases, the chain will need to be replaced. The chainrings and cogs may also need to be replaced if they are damaged.

If you ride your bike regularly, it is important to inspect the drivetrain often. This will help you to identify any damage early so that it can be repaired before it causes the chain to skip.

3- Gear indexing issues

If your bike’s gears are not properly indexed, it can cause the chain to slip or come off while under load. This is because the chain is not able to engage properly with the teeth on the gears. This can be caused by a number of things, including a misaligned derailleur, bent chainrings, or even a dirty chain.

How to fix it?

If you suspect that gear indexing issues are to blame for your chain slipping, there are a few things you can do to fix the problem. First, make sure that your derailleur is properly aligned. You can do this by adjusting the limit screws on the derailleur until the chain is able to shift smoothly between the gears.

If your chainrings are bent, you will need to replace them. This is usually not a difficult or expensive task, but it is something that you should take to a bike shop if you are not comfortable doing it yourself.

Finally, make sure that your chain is clean and well-lubricated. A dirty or dry chain is much more likely to slip or come off than a clean and lubricated one. You can clean your chain with a simple degreaser and then lubricate it with a quality bike chain lubricant.

4- Mismatched drivetrain

A chain skipping under load can be caused by a number of factors, but one of the most common is mismatched drivetrain components. When the chainrings and cogs are not the same sizes, the chain can skip over the teeth and cause the bike to lurch forward. 

This can be extremely dangerous, especially if you are going downhill, so it’s important to make sure your drivetrain is properly matched before you ride.

There are a few ways to tell if your drivetrain is mismatched. First, check the size of the chainrings. If they are different sizes, they will need to be replaced with a matching set. 

Next, look at the cogs on the rear wheel. If they are different sizes, you will need to either replace them with a matching set or get a new rear wheel that is the correct size. 

Finally, look at the chain itself. If it is too loose or too tight, it can cause the chain to skip. If you are unsure of the proper tension, consult a bike mechanic.

How to fix it?

Once you have verified that your drivetrain is mismatched, you need to take action to fix the problem. The best way to do this is to replace the entire drivetrain with a new one that is properly matched. This can be expensive, but it is the best way to ensure that your bike will ride smoothly and safely.

5- When something is wrong with the bushing/bushing interface

One of the most common reasons for a bicycle chain to jump under load is due to a problem with the bushing to-bushing interface. This can occur if the bushing is not seated properly in the frame, or if the bushing is damaged. 

If the bushing is not seated properly, it can cause the chain to rub against the frame and eventually jump. If the bushing is damaged, it can cause the chain to jump because it is not able to grip the chain properly.

6- Worn cassette

If your bike’s chain is skipping under load, it’s possible that your cassette is worn. A worn cassette is one of the most common causes of chain skipping, and it can happen even to experienced riders.

The cassette is the cluster of gears on the rear wheel of your bike, and it wears out over time use. As the cassette wears, the teeth on the gears become less grabby, and the chain can start to slip. This is especially noticeable when you’re pedaling hard, such as when you’re going up a hill.

If you think your cassette might be worn, there are a few ways to check it. One is to look at the teeth of the gears. If they’re noticeably pointy, they’re probably worn. Another way to check is to see if the chain is slipping when you’re pedaling hard. If it is, it’s likely that your cassette is worn.

How to fix it?

If your cassette is worn, the best thing to do is to replace it. This is a relatively easy and inexpensive fix, and it will make your bike ride much smoother.

7- A worn or damaged chain

If you’re experiencing your bike chain skipping under load, it’s likely because your chain is worn. A chain is considered worn when any of its rollers are more than 0.5% worn, or when one of its pins is more than 0.8% worn. 

When a chain skipping occurs, it’s usually because the chain has stretched to the point where it can no longer properly engage the teeth of the corset or chainring. The chain will also skip if the corset or chainring is damaged or if the chain is not properly lubricated.

How to fix it?

If you think your chain might be worn, the best way to check is with a chain wear indicator. This is a simple tool that you can purchase at most bike shops. To use it, you simply place the tool on the chain and see if the 0.5% or 0.8% line lines up with any of the rollers or pins. If it does, then it’s time to replace your chain.

If you’re unsure of how to replace your chain or don’t have the time to do it yourself, most bike shops will be happy to do it for you. Just be sure to bring your old chain with you so they can properly size the new one.

8- Worn or damaged sprockets

Another common reason for a bike chain to skip under load is because the sprockets are worn out or damaged. Just like a chain, sprockets can become stretched or damaged from use. Worn sprockets will cause the chain to slip and will also result in a loss of power.

9- Dirty chain

A dirty chain can also cause skipping. Dirt and grit can build up on the chain and cause it to slip. A clean chain will run smoother and is less likely to skip.

Why Does My Chain Slip Under Pressure?

If your chain slips under pressure, it is probably because the chain is worn and needs to be replaced. A chain can stretch over time, and as it stretches, it becomes weaker and more prone to slipping. Chains also wear out from dirt and debris, so it is important to keep the chain clean and lubricated.

If you suspect your chain is worn, the best way to check is with a chain wear indicator. This is a simple tool that can be purchased at most bike stores. To use it, simply place the chain wear indicator on the chain and see if the chain wraps around the tool. If the chain wraps around the tool, it is time to replace the chain.

If the chain slips, it is also important to check the cassette and chainrings for wear. If these parts are worn, they will also need to be replaced.

It is important to detect chain wear early, as it can cause damage to drivetrain components. Replacing the chain regularly is the best way to prevent such damage.

Why Does My Bike Chain Skip When I Pedal Hard?

There are several reasons why your bike chain may jump when you pedal hard. The most common reason is that the chain is too loose. When the chain is slack, it can come off the teeth of the gears, which will cause it to jump.

Another common reason is a dirty chain. A dirty chain can also cause it to jump because dirt and grime can build up on the chain and cause it to slip.

If your chain jumps, the first thing you should do is check to see if it is too loose. If it is, you will need to tighten it. This is a fairly simple process, and you can find instructions in your bike’s manual.

If the chain is dirty, you will need to clean it. You can do this with a chain cleaner or by simply wiping it down with a rag. If you clean it regularly, you can avoid this problem.

If you are still having problems, there are other things you can try. One of them is to adjust the derailleur. This is the part of your bike that controls the chain, and if it is not adjusted properly, it can cause the chain to jump.

Another option is to use a different type of chain lube. Some lubricants are more effective than others, so you may have to experiment to find the one that works best for you.

If you pedal hard and your chain keeps jumping, there may be a problem with your bike’s drivetrain. This is the part of the bike that includes the chain, gears, and pedals. If there is a problem with any of these parts, it can cause the chain to jump. You will need to take your bike to a mechanic to have it checked.

If you pedal hard and the chain keeps jumping, there may be a problem with the bike’s drivetrain. This is the part of the bike that includes the chain, gears, and pedals. If there is a problem with any of these parts, it can cause the chain to jump. You will need to take your bike to a mechanic to have it checked.

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Author
Allen
Hi, I'm the initiator and writer of this blog. Bikes were and will be my first love, and my favorite hobby, that's why I decided to start this blog and write about my discoveries and techniques to improve my bikes or repair them.

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