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Why Does My Bike Chain Keep Popping? – Causes & How to Fix


Written by Gary Johnson / Fact checked by Henry Speciale

why does my bike chain keep popping

Riding your bicycle is all fun and games, not until you hear your bike chain clicking, and the next thing you know it, your bike chain starts popping off.

You may question, why does my bike chain keep popping? To answer simply, the reason why you may experience that very common bike chain problem is either because of worn-out and damaged chains, poor shifting system, gear misalignment, and too loose or too tight chains.

That’s the shortest answer you’re looking for. But of course, there’s more to it if you want to figure out how to repair it. Read on!

List of Reasons Why Your Bike Chain Keeps Falling Off

Reason #1 – Worn-out chains

Worn-out-chains-cause-Your-Bike-Chain-Keeps-Falling-Off

This is one of the most typical reasons a bike chain keeps coming off. Despite a chain’s material that attributes to its durability, there is no doubt there is still a possibility of wear and tear, especially if it’s been used for so long.

When it comes to worn-out chains, it’s not the chain links that get worn out. Usually, the roller bearings and the pivots attaching the links together suffer from too much friction over time.

This worn-out system then results in a chain stretch. A chain stretch is when your bike chain becomes longer as the rollers develop small gaps that slightly lengthen the chain.

Reason #2 – Damaged chains

Damaged-chains-cause-Your-Bike-Chain-Keeps-Falling-Off

Even the most unnoticeable out-of-shape link can cause the entire chain to malfunction. If there has been an instance that your chain has fallen off the cassette, you should check if any links have been bent.

Actually, it happens when we attempt to get our stuck chain out of the wheel spokes, cassette, or guide wheels, etc.

So, be careful not to use too much force when fixing your chain:

  • If you find your chain stuck between the derailleur, removing it without extra caution can cause your chain to bend.
  • So remember that when doing so, don’t tug or pull the entire chain. Please focus on the stuck area and gently pull it to loosen the stuck parts.
  • If you’re still having trouble with it, try to remove the wheels. This does the job of lessening some gear pressure. The last resort for you to take if the chains remain stuck is to get your cassette tool & use it accordingly to remove the chain.
  • The next step is to straighten back the bent chain link. The short-term solution for this is taking the bent part found on the pins of the link and using pliers to straighten it back.

Reason #3 – Poor shift system

Poor-shift-system-cause-Your-Bike-Chain-Keeps-Falling-Off

A bike’s shifting system that isn’t at its best can result in a tire popping sound which will eventually result in bad chain problems.

So, if you ask, why is my bike making noise when pedaling?, here are some of the issues that cause a poor shift system:

  • A low-quality shifter
  • A misaligned rear derailleur
  • A bad derailleur hanger
  • A loose-tension shifting cable.

Reason #4 – Incompatible parts

Incompatible-parts-cause-Your-Bike-Chain-Keeps-Falling-Off

Bikes are known for having parts that can be mixed and matched. Not all functional parts can fit different bikes and their brands.

Using incompatible parts for your bike, especially if chains that may be too loose or tight, may result in them slipping and popping.

How to Diagnose the Cause of the Bike Chain Popping and Fix It

#1: Check the chain’s length

Check-the-chain’s-length-to-Diagnose-the-Cause-of-the-Bike-Chain-Popping-and-Fix-It

If your bike has been with you for ages, then you might want to check out if the chain appears longer. If it does, then this is the reason why the bike chain came off bike

If your chain is already worn out, the best and safer solution is to simply replace your chain with newer & more durable ones. The cost of new bike chains may range from $15 to $60 depending on the shift quality & its performance.

#2: Check for damage

Check-for-damage-to-Diagnose-the-Cause-of-the-Bike-Chain-Popping-and-Fix-It

If your chain may look rusty or simply old. Wear and tear is another possible cause of your bike chain jumping.

#3: Check the shift system

Check-the-shift-system-to-Diagnose-the-Cause-of-the-Bike-Chain-Popping-and-Fix-It

  • The shifter – if you notice uneven gear shifts with your bike chain making noise when pedaling.
  • Rear derailleur – if your rear derailleur is inoperable with its cassette cogs which results in the chain slipping.
  • Derailleur hanger – Check the bike’s behind & inspect if the hanger is aligned to the wheel, if the derailleurs and pulleys don’t look parallel & slightly bent.
  • Shifting cable – If your shifting cables have been in use for long years and you feel a sluggish feeling when you hit the brakes or when you can’t hit them at all.

How to fix these issues?

– A low-quality shifter

For a low-quality shifter, you may want to replace the levers, twist grips, or derailleurs with more high-quality shifting gears.

– A misaligned rear derailleur

Take the chain, align it into the biggest chainring with the smallest cog, and loosen up the bolt that attaches to the derailleur.

Find the high and low adjusters on the derailleur marked as “H” or “L.” Next, turn the high-gear screw and only stop turning when the jockey pulleys finally align with the smallest cog.

Please test it out & adjust until it runs smoothly again.

– A bad derailleur hanger

You may either replace the derailleur hanger or simply bend it back by doing the following steps:

  1. First remove the rear derailleur and insert the head of your derailleur alignment gauge inside the hanger.
  2. Use your derailleur gauge to check the alignment of the derailleur. The distance of the wheel should be equal from the top to the bottom. Do this by pushing the tool’s rod up against the wheel at the top and bottom.
  3. Use your derailleur alignment gauge to straighten your derailleur by gently pulling it down as it bends to your likeness.
  4. Following the same steps, straighten your derailleur again. This time, horizontally. Once your hanger appears also to be aligned both vertically and horizontally, then it’s already straight.
  5. Install back your rear derailleur. Check & assess all parts.

– A loose tension shifting cable

You can tighten it by following these steps:

  1. Shift the gear to the highest or lowest, depending on which makes it even looser.
  2. Place your barrel shifter slightly out of the way at the shifter.
  3. Unfasten the pinch bolt on the derailleur, get rid of all the slack, and re-tighten the pinch bolt
  4. Grab your barrel adjuster & test out if there are any tension problems.

#4 Double-check the newly-replaced parts

Double-check-the-newly-replaced-parts

If you have just reinstalled new bike parts and you want to know how to know if the parts are compatible with one another, you can always test them out.

However, you can always check your bike brand’s website if you don’t want to take the risk. Typically, bike manufacturers provide stock spec archives. These show you a bike’s basic specification sheet, which may include parts compatible with your bike.

You may also search for a bike part compatibility checker to make your life easier. Websites like these allow you to find out which specific parts & accessories are compatible with your bike.

Tips to Prevent Your Bike Chain From Popping

Tips-to-Prevent-Your-Bike-Chain-From-Popping

Tip #1 – Always degrease your chain & use a brush

Tip #2 – Wash your chain from time to time using soap and water

Tip #3 – Apply lube but don’t go overboard

Tip #4 – Always adjust your cable tensions

Tip #5 – Always check if your derailleur is aligned

Frequently Asked Questions

bike-chain-skipping-when-pedaling-hard

How many miles does a bike chain last?

Bike chains last an average of about 2,000 to 3,000 miles. Of course, this depends on how you ride your bike, the daily terrain, and the bike’s quality.

How tight should a bicycle chain be?

The tightness of your bike chain should only allow you to move about half an inch. Therefore, always check if you should tighten or loosen it to get this perfect tightness for a smooth and safe ride.

How much does it cost to fix a bike chain that keeps popping?

For a bike chain replacement, the cost of a bike chain is around $15 – $60. Add this to the cost of labor if you’re getting it fixed by a professional. You can get your existing bike chain fixed on your own, which may cost you roughly $25 to $50 in purchasing tools.

How often should I check my bike chain?

It’s good to check and adjust your bike chain for every 500-mile ride. If you use your bike regularly and may be prone to dirt and grime, check it more often.

How do I know if my bike chain needs replacing?

If you spot any damage on your bike, whether it’s cracked or bent, you may have to replace it. If you notice your bike chain skipping when pedaling hard & still keeps doing so after many repairs, then this is another sign.

Conclusion

No matter how much you take care of your bike chain, and regardless of how good it is, whether it’s a mini bike chain or a regular one, you may still experience some problems here and there over the years.

So if you’re wondering, “why does my bike chain keep popping?” it’s normal, and it happens but of course, there are more reasons why. And now that you know what & how to give solutions to these, you know what to do & won’t have to worry about a thing!

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