Written By: Jonathan
Fact Checked By: Caroline Dezendorf
Reviewed By: Matt Tanner
A slippery bicycle chain is very frustrating, but more than that, it can be dangerous and disruptive to your trip.
It doesn’t matter where you’re driving, whether you’re passing through town or heading on a weekend trail, an unexpected chain slip can cause you to lose control and fall over.
There are 6 common issues that can be responsible for chain slippage problems.
In this guide, you will learn about the actual problem, how to diagnose it correctly and the best possible solution based on the specific issue to get your bicycle running smoothly again.
Firstly, If your bicycle chain slips frequently, check for these 6 causes:
- Worn-Out Chain or Cassette
- Stretched Chain
- Loose Derailleur or Misalignment
- Dirty or Poorly Lubricated Chain
- Wrong Gear Combinations
- Faulty Chainring Teeth.
Common Reasons Your Bicycle Chain Keeps Slipping
Chain slippage is a sign that something is wrong with your bicycle.
This is so common so don’t worry too much about it, because over time, components wear out, become out of adjustment, and stretch, resulting in poor gear engagement and unpredictable chain behavior.
Let’s take a look at the most common reasons behind a slipping chain, ranging from minor maintenance oversights to more serious financial solutions.
| Cause | Description | Solution |
|---|---|---|
| Worn-Out Chain or Cassette | Typically, the teeth and links wear out over time, leading to poor engagement. | Inspect for wear; replace chain/cassette or both as necessary. |
| Stretched Chain | With excessive use the chain becomes stretched and doesn’t fits properly into the gears. | Measure chain stretch; replace if wear exceeds recommended limit. |
| Loose Derailleur or Misalignment | Typically a misaligned or loose derailleur causes shifting problems and slippage. | You just need to adjust the derailleur alignment and cable tension. |
| Dirty or Poorly Lubricated Chain | It is most common that dirt and lack of lubrication causes friction and bad chain movement. | Simply clean thoroughly and then apply bike-specific chain lubricant. |
| Wrong Gear Combinations | Shifting from first to last gear or something like that causes cross-chaining, which puts stress on the drivetrain and can cause misalignment. | You must use straight chain lines; don’t use extreme gear combinations. |
| Faulty Chainring Teeth | When you see bent or worn teeth that can’t grip the chain properly. | Simply inspect visually for damaged or worn chain rings and replace them. |
Worn-Out Chain or Cassette
The most common reason behind a bicycle chain slipping is a worn-out chain or cassette, as it is obvious that as you ride it over time, the chain gradually stretches and the teeth of the cassette wear down which actually leads to poor engagement between the two components.
This wear causes slipping, especially whenever you apply load or change gears.
Solution: Just clean and lube it, and if it’s still slipping while riding, it’s probably time to measure if the chain is stretched, and also inspect the cassette for signs of rounded or shark’s tooth shaped teeth. Now it is time to replace these parts and this is necessary for safe and smooth traveling.
Read More:
Stretched Chain
To be honest, a stretched chain is a subtle but important problem that can also cause chain slippage in a bicycle.
Yes, the chain does not physically stretch, but the internal pins and bushings wear out which increases the overall length.
This results in inconsistent power transfer and the chain skips frequently, especially when you pedal hard or apply more pressure.
As if the chain is too loose which actually result from incorrect length or wheel misplacement that kind of chain can slip when torque is applied.[¹]
Solution: If it’s not maintained or checked properly, as you can do with a chain checker tool to spot the problem quickly, it can lead to damage to more expensive parts like the cassette or chain rings.
Loose Derailleur or Misalignment
Shifting performance also depends on the derailleur, so a loose or misaligned derailleur may cause the chain to slip.
The role of the derailleur is to move the chain accurately from one gear to the next, so if it is not correctly aligned or securely mounted, the chain will not seat correctly on the cogs.
This can be noticed when shifting gears hesitantly, skipping gears, or abrupt gear shifting under pressure.
And misalignment can be caused by a bent derailleur hanger, incorrect cable tension or worn pivot points.
Solution: To solve this problem you usually need to fine-tune the derailleur or in the worst case you need to completely replace the damaged components to restore reliable and clear gear shifting without slipping.
Dirty or Poorly Lubricated Chain
This usually happens when the chain is clogged with dirt, grime or lacks proper lubrication, which reduces performance and causes the chain to slip.
Additionally, accumulated dirt and other debris causes friction between the chain and cassette, reducing smooth engagement and increasing wear on both components.
So without proper lubrication, the direct metal-to-metal contact increases, resulting in stiffening of the chain links.
Solution: To solve this problem you need regular cleaning and proper lubrication: which is the only thing that can prevent the slipping, even it increases the lifespan of the components. Bicycle-specific degreasers are available, containing the most appropriate type of lubricant for your bicycle, matched to your riding conditions.
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Wrong Gear Combinations
In addition to broken and worn components, using incompatible and extreme gear combinations also causes chain spillage.
Because changing the chain from the smallest chain ring to the largest chain ring can put too much stress on the drivetrain and thus ruin the chain alignment.
This is also called cross-chaining and can cause expensive damage to the chain and derailleurs, often resulting in slippage, noise and accelerated wear.
Yes, drivetrains are being built nowadays that can handle different gear ratios, but constantly doing Inappropriate combinations affects the mechanical efficiency of the components.
Solution: You can shift into more linear, mostly balanced gears, which will definitely help in smooth operation and increase component life.
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Faulty Chainring Teeth
It is obvious that the teeth on the chainring help keep the chain in one place while riding.
Therefore, if the teeth become worn, broken or bent, it is natural for the chain to slip.
This is usually caused by using from long time, lack of attention, or always using a stretched chain.
Therefore, when you pedal faster, such as when going uphill or need to increase the speed of the bicycle, the chain slips.
You can easily identify worn teeth because they look sharp, hooked or uneven.
Solution: And the only solution is to replace the damaged chain ring to fix the slippage problem and also prevent other parts of the bicycle from wearing out prematurely.
Quick Solutions for a Slipping Bicycle Chain
A chain slipping is utterly frustrating, but it’s even more concerning from a safety perspective.
It’s usually easy to fix if you take the right approach, and these are effective solutions.
1. Adjusting the Rear Derailleur
To adjust the rear derailleur you need to turn the barrel adjuster on the derailleur slightly so that it adjusts the tension: usually you have to turn it counterclockwise to tighten the cable and this actually helps to align the gears better.
Also, you need to check the high and low limit screws so you can make sure the derailleur isn’t shifting to a higher or lower gear than it should be.
Even if the chain is correctly tensioned, it can still slip if the derailleur hanger is bent or the pulley alignment is incorrect, and this is most commonly observed under heavy pedaling.[²]
So you will need to straighten or replace it for accurate shifting.
2. Replacing the Chain or Cassette
To replace a chain or cassette you’ll first need to measure the chain with a chain checker tool, and if you find it’s stretched more than 0.5% on a newer drivetrain like an 11-speed, it’s time to replace it rather than fix it.
Moreover, if you notice that the teeth of the cassette are really worn out or damaged then you need to replace it as well.
So the bottom line is that you should always replace a worn chain before it damages the cassette, because if you drive with a stretched chain for too long you’ll have to replace both the chain and the cassette.
3. Cleaning and Lubricating Your Drivetrain
When you notice a dirty drivetrain with all kinds of grime on the chain or cassette, you need to clean both the chain and the cassette with the help of a bike-specific degreaser and a stiff brush.
Just wash it thoroughly and then let it dry completely, and after that you will need to apply a quality chain lubricant.
Additionally, you will also need to ensure that any excess grease is wiped off and this is also important to avoid attracting more dirt over time.
A bicycle chain does indeed stretch over time and will often last about 2,000 to 3,000 miles, but if they are in harsh conditions or not properly maintained they can wear out in as little as 500 miles.[³]
Simply perform regular chain maintenance every 100 to 150 miles or after wet riding, this will keep the chain shifting smooth and the parts working efficiently.
4. Chainring or Crankset Replacement
When you notice that the chainring teeth are sharp, crooked, or broken, you need to replace the chainring immediately.
And if you have an integrated crankset you may actually have to replace the whole assembly,
Besides this, you should also check if the crank arm bolts and bottom bracket are properly tightened as looseness can also cause the chain to slip.
Conclusion On Why Does My Bicycle Chain Keep Slipping?
A bicycle chain slipping is very frustrating, no doubt about it, but only by knowing the symptoms can you understand the causes and fix it or prevent it for the next time.
So, in this guide we have addresses 6 types of causes and steps to restore smooth, reliable performance.
Moreover, we have also included quick solutions that can prevent the chains from slipping and make them future-proof as well.
Let me know if you have further questions regarding this.
Frequently Asked Questions
Q1. What is the best lubricant for bicycle chains?
Answer: If you don’t want to get too technical with bicycle lube, you can use Smoove Universal Chain Lube, as it is a wax-based product, but you will need to clean the chain before applying this lubricant. It makes the ride smooth and efficient.
Q2. How to tell if your bike chain needs lube?
Answer: When your bike chain looks dull, dusty or rusty, it means you need lubrication. Also, if you hear noises during normal pedaling and have a bad pedaling experience, it is time to properly lubricate the chain.
Q3. Do pro cyclists use waxed chains?
Answer: Yes, many professional cyclists and even racing teams use waxed chains to reduce friction compared to traditional oil-based lubricants when their focus is on performance.
Q4. Which oil can be used as chain lube?
Answer: Not all oils are suitable to use as chain lube, so it’s ideal if you use a bike-specific chain lube, but you can use a light oil like sewing machine oil or 3-in-1 oil to get the job done temporarily.
References:
[1] iFixit Troubleshooting. Bicycle Chain Slips – Causes & Fixes.
https://www.ifixit.com/Troubleshooting/Bicycle/Chain%2BSlips/535147
[2] Bike Chain Slipping? 10 Reasons and Fixes
https://efeducationtibcosvb.com/bike-chain-slipping-reasons-and-fixes/
[3] Selle Anatomica. Factors That Affect the Life of Your Bike Chain.
https://selleanatomica.com/blogs/homepage-blog/factors-that-affect-the-life-of-your-bike-chain
Jonathan, the passionate owner of Bicycle Time, brings a lifelong love for bikes and automotive craftsmanship, that reflects into every corner of the shop. With deep passion in both cycling and automotive accessories, Jonathan is more than just an expert.