Why Does My BMX Chain Keeps Snapping?

BMX bikes are undeniably hardy. But even so, their chains are just as vulnerable to snapping like those of other bikes. So, are you asking, ‘why does my BMX chain keeps snapping?’

Your BMX bike chain keeps snapping because it’s rusty, shorter, loose, excessively clogged, the wrong size, wrongly installed, or worn out. It could also be because of a damaged chainring or sprocket, forceful pedaling, or heavy impact.

So, you must look at all these possibilities as one of them is why your BMX chain keeps falling off. Lucky for you, I’ll explain all the possible causes and suggest the best prevention tips and fix.

My goal is to enable you to not only fix your snapped BMX chain but also to stop the trend.

Here we go! 

how do you fix a snapping chain on a bmx bike

10 Possible Reasons Your BMX Chain Keeps Snapping

Here are ten possible reasons why your BMX chain keeps breaking off even after fixing:

1. Your BMX Chain Might Be Rusty

Watch out for rust, as it’s an enemy to your chain and other metallic bike parts. Rust, which forms from exposing metal surfaces to wet conditions, eat the chainrings, causing them to weaken and break off.

Prevention Tip:

While you cannot do anything to save your chain after it rusts, you can prevent rust from forming by ensuring you dry the chain after wetness exposure.

You can also do it by spraying an effective WD-40 spray such as the WD40 Specialist Bike Chain Lube (View on Amazon). This lubricant can also serve as your chain cleaner and is generally effective against rust.    

WD40 Specialist Bike Chain Lube

2. Your BMX Chain Might Be Shorter

If you use a shorter chain, you’ll likely apply too much force on the pedals that impact the chain. And before you know it, the excess pressure causes the chain to snap off.

Prevention Tip:

Ensure your BMX chain is not too tight or too short. If it is, you should adjust its tension or get a new chain.  

3. Your Bike Chain Might Be Loose

Your BMX chain requires the correct tension to propel the bike properly. If it’s not tight enough, the chances are that it’ll drop off the bike’s sprocket and snap off.

Prevention Tip:

Always ensure you tighten your BMX chain correctly to give it the correct tension. It should have a half-inch vertical deflection, which prevents it from rubbing against the chainstays.

4. Your Bike Chain Might Be Excessively Clogged

This probably comes as a surprise, but too much debris, grime, and dirt can weaken your chain and cause it to break. They may slowly grind the chain links or get locked into the links, causing the chain to snap.

Prevention Tip:

Learn to clean your bike chain as often as possible. You can do that using kerosene or just any effective chain lubricant. A perfect pick is the Muc-Off Dry Lube (View on Amazon).

Not only does it clean the chain, but it also protects against dirt, excessive friction, and harsh weather.

Muc-Off Dry Lube

5. Your BMX Chain Might Be the Wrong Size

This is likely to happen when you shop for your BMX bike chain secondhand. If you fit a BMX chain that doesn’t match your bike, it won’t work correctly, but that’s not the worst.

The worst thing is that the chain may snap off and rub against the chainstays. And if it’s too small, it’ll become too tight, compelling you to use much force, which could break it.

Prevention Tip:

Ensure you shop wisely for the chain even if you go for secondhand. It’s worth knowing your BMX bike chain size to avoid making a mistake, and more importantly, don’t use a chain intended for a non-BMX bike.

6. Your Bike Chain Might Be Wrongly Installed

If it’s incorrectly fitted, you cannot expect your BMX chain to work. The worst that can happen is that the chain can start snapping off until you fit it correctly.

The good thing about this is that you don’t need to be an expert to determine that the chain is wrongly installed. You can know it by just looking at it.

Prevention Tip:

Don’t be in a hurry to fit the chain once it falls off. You should ensure you fit it accordingly before you can jump onto the BMX and ride off.

7. Your Bike Chain Might Be Worn Out (Stretched)

You’ve to consider if the bike chain has seen its better days. Quality bike chains usually last 2000-3000 miles depending on usage, including BMX chains.

So, if you have used it for more than 2,000 miles or probably, 3-4 years, then it’s the right time to replace it. If you are not sure about it, use a chain wear checker (View on Amazon) to see the level of wear or chain stretch.

chain wear checker

8. Damaged Chainring or Sprocket

If the teeth of the chainring are bent or damaged, they’ll aggressively ride against the chain and weaken it. And even if the chain will not snap off, the chances are that it’ll keep slipping off.

Prevention Tip:

Stop your bike chain from slipping off or snapping off by straightening the chainring or sprocket if they are bent. Make it a habit to check for signs of damage on the chainring or sprocket.

9. Forceful Pedaling

There are several reasons why BMX bikers find themselves pedaling hard. Often, it’s because they want to go faster, but sometimes, it’s due to a tight chain.

In either case, forceful pedaling can break a BMX chain.

Prevention Tip:

Avoid pedaling too hard, which puts excessive pressure on the pedals and the chain. Also, ensure you use the correct chain tension to save the chain from tightening excessively.

10.  Heavy Impact

Since BMX biking is a heavy-impact sport, there is always the chance of the chain hitting something hard like a rock and snapping off. While this is not common, it’s likely to happen if you are an overly aggressive rider.

Prevention Tip:

Avoid riding on rough roads as your BMX chain may rub against something and snap off. And if you must go through obstacles, do it gently to avoid chain snapping.

How Do You Fix a Snapping Chain On A BMX Bike?

You usually have two choices when dealing with a broken BMX chain. You can fix the chain with a spare link (more so a master link) or without it.

Let’s look at both options:  

Option 1 – How to Fix a Snapping BMX Chain with A Master Link?

If you want to retain the chain’s original length, adding a new link to replace the broken one is advisable. Consider getting a master link (View on Amazon).

master link

Other than the master link, you’ll need pliers to perform this task. Here’s how to go about it:

  • Take out your master link and face it in the right direction
  • Unlock the two halves of your master link by pinching them together
  • Take each of the master link’s halves and push them through the chain’s holes on opposite ends
  • Bring your chain together and align its holes before passing the pin through them
  • Join the chain to the master link and use pliers to click the pins perfectly in position
  • That’s it, and your chain will be as good as new!

Option 2 – How to Fix a Snapping BMX Chain Without a Master Link?

If you don’t have an extra master link, you can still fix your broken BMX chain. This is, however, a temporary fix as it means you’ll have a slightly shorter and tighter chain.

It also means that it’s not the best fix when the reason behind the snapping is a tighter chain. Overall, you’ll need a chain tool to perform this DIY fix.

Here’s how to go about it:

  • Stop pedaling immediately after the chain snaps and turn the bike upside down
  • Push the pin through the holes of the chain using the chain tool
  • Ensure the pin fits well, and the interconnected links form a perfect connection
  • Go ahead and lubricate your BMX chain before riding the bike

People Also Ask

1. Why Does My BMX Bike Chain Keep Slipping?

There are several reasons why your BMX chain keeps slipping off. They include:

  • Stretched chain
  • Loose chain
  • Wrong chain size
  • A worn-out or excessively dirty drivetrain
  • Misaligned or damaged sprocket or chainring
  • Forceful pedaling
  • Clogged chain

2. Why Does My BMX Chain Keep Coming Loose?

Your BMX chain keeps coming loose because it’s probably too old and thus stretched. Bicycle chains typically stretch when they are two old, and you can tell that using a chain wear checker tool. If the chain is too stretched, then you should replace it.

3. Why Does My BMX Chain Keep Breaking?

Your BMX chain keeps breaking because it’s too tight, too loose, rusty, or worn out. But at times, it could be due to a damaged sprocket or chainring, heavy impact, or forceful pedaling. Also, check for wrong installation or a case of using the wrong chain size.

4. How Do You Keep a Chain Form Snapping?

You can keep a chain from snapping using these tips:

  • Properly lubricate the chain
  • Use the correct chain size
  • Go easy on the pedals – don’t use much force
  • Invest in a quality bicycle chain
  • Avoid overtightening the chain

5. What Happens If BMX Chain Is Too Tight?

If your BMX chain is too tight, there’s always the risk of being compelled to forcefully pedal, and you may break the chain. Also, since the chain connects movable parts, the parts are likely to wear down from excessive friction.

6. How Tight Should A BMX Chain Be?

Your BMX chain should have a ½ inch vertical deflection. The chain should move up and down by about a half-inch. If it’s too loose or too tight, it’s likely to snap off.

Why Does My BMX Chain Keeps Snapping? Closing Remarks?

As discussed, your BMX chain could be snapping off for different reasons. It could be that the bike chain is loose, too tight, dirty, rusty, wrong size, or old. It could also be an issue with a damaged chainring or sprocket, forceful pedaling, or heavy impact.

The good news is that all ten possibilities are fixable!