Reasons Why Your Bike Chain Keeps Coming off? (for Single Speed Bikes)

Having your trusty bike break down while you’re in a hurry can be a daunting experience. Sometimes it seems like no matter what you do, the bike chain keeps coming off your single-speed bike. If ignored, the situation can quickly escalate from being just a minor annoyance to outright dangerous.

I’ll help you understand why a single-speed bike chain keeps popping from its rail. After identifying the problem, it’s easy to fix it once and for all. You’d be pleased to hear that most issues can be fixed at your garage without professional help.

Why Does My Single-Speed Bike Chain Keeps falling?

Let’s explore some of the most common reasons for single-speed bike chains coming off and give you easy fixes to make your future experience on the road more pleasant.

Stretched Chain

With heavy usage and vigorous pedaling, your single-speed bike chain might become loose. The links along the chain start opening up as they cycle from one cog tooth to the next. The result is a chain that’s too long and can easily come off the front cog, giving you unwanted troubles on the road.

Inspect your bike’s chain and check for any sag between the chain ring and rear cog. Put the bike on a stand where it stands straight up, a saggy chain can be easily identified when there is too much give on the chain in the middle.

Fixing a Stretched Chain

Each bike chain has an estimated riding distance before it shows signs of aging. And chains can were out quicker or slower depending on how the bike is used and maintained.

All you need to do is replace your stretched chain with a new one, and voila, your bike is as good as new.

  1. Remove the old chain using a chain remover tool
  2. Make sure you’re getting the right-sized chain, if not make sure to cut the new chain to the same length as the old one using the chain remover tool.
  3. Put the new on back on both the front and back cogs and connect the using the bicycle chain links that came with the new chain.
  4. These chain links usually just snap into place.

Worn Out or Bent Spikes on Chainring or Rear Sprocket

Next up is checking your bike’s cogs. Bring your single-speed bike to its side and inspect the teeth on the cogs and the rear sprocket. As your bike ages, the cog might crack or show signs of rust. That’s not all; the cog teeth wear out and become blunt. This makes holding the bike chain in place an impossible task as the cog teeth have become blunt.

Fixing This Issue

If your problem arises from some bent cog teeth, you can simply use a plier to bring the bent spikes back in place. However, you might need to replace the entire cog if you come across many missed spikes or if the metal body itself is damaged or cracked.

It’s also worth noting that a rust remover can come in handy in many situations, especially if the rust creeps up, reaching the spikes and affecting the chain’s movement along its rail.

Loose or Misaligned DriveTrain

The intricate system responsible for your bike’s movement is called the drivetrain. This includes the pedals, chain, and cog teeth. The drivetrain’s stability ensures the smooth motion of the single-speed bike chain during pedaling.

With that being said, if the screws used to keep the drivetrain in place become loose, the entire system wobbles around as you pedal. This increases the chance of the bike chain coming off your bike.

Fix for This Issue

Get your Allen Key ready, as all you need to do is re-fasten the screws and nuts on the components to ensure each part sits firmly in place. Think of the drivetrain as the bike’s engine so it is critical to fix any issues there.

You might need a set of screwdrivers as well to fasten the screws holding the bike’s cog, pedals, and derailleur.

Bike Chain with Cassette and derailleur with a scooter in the background

Rusted and Worn Out Chain

We’ve already touched on how a rusty cog can be an issue. The same goes for rusty and worn-out chains! If your bike was left unattended in your garage for years, rust spares no chance to take over.

In this case, the rusty chain can’t slide as easily along the cog spikes. The whole system becomes stiff, which translates into an unpredictable riding experience.

How to Fix a Rusted or Worn-Out Chain

Using a rust remover does the trick, especially if you’re dealing with extensive rust. You’ll also need to make sure your bike chain is well-lubricated all the time. A good quality lubricant should reduce the friction between the chain links, giving you a more pleasant driving experience.

If your bike chain is worn out beyond repair, maybe it’s time to slip in a brand-new chain that won’t come off when you backpedal.

Bent Frame

A bike’s frame is the backbone of the bike; all the components are connected to the frame. If your frame is bent or damaged, the chain might become loose as the distance between the cogs is reduced.

Check your bike’s frame for any dents or breaks now and then. You shouldn’t sleep on inspecting your bike’s frame, especially after hitting a bump in the road or getting into a crash.

Can You Fix this Issue?

If you notice any misalignment in the wheels, pedals, or other bike components, you should get your bike checked by a professional. 

Caring for Your Chains and Drive Train

Good housekeeping and maintenance of the bike go a long way to keep the bike running in good condition. Here are some tips to take better care of your bike’s chains and drive train:

  • Ensure the tires are running at the right air pressure.
  • You shouldn’t overlook the bike chain’s lubrication. All you need to do is apply a little lubricant along the rear sprockets and the front cog. Then, move the pedal to ensure the oil gets in between the bike chain links and smoothes out any rough edges!

Related Problems and Fixes

Let’s see similar issues on other bikes and their solutions.

Bike Chain Keeps Coming off Kid’s Bike

Unlike adult bikes that wear out due to rigorous pedaling and potentially heavy riders, a kid’s bike could have a sloppy chain for a different reason, a dirty chain. The situation is fairly simple and requires a good bike wash to remove the dirt clogging the chain and spikes.

Bike Chain Keeps Falling off Beach Cruiser

Beach cruiser bikes could accumulate rust due to constant exposure to the salty ocean or sea breeze. The chains can be rusty and can wear out quicker than other bikes. You’ll want to ensure the gears are as far away from salty water as possible. And clean sand from the chains often. Applying an anti-rust paint could also come in handy.

Chain Keeps Coming off Bike When Changing Gears

Unlike a single-speed bike with a single-cog wheel, bikes with gears allow the chain to move from one cog to next for a more efficient ride. If you’re not well versed in how the combination for changing gears works, you might give opposing commands to the rear and front gears, resulting in the whole system falling apart and your bike chain coming off!

Final Thoughts

I hope this article helped you fix your bike chain issue. let me know your experience on how well it went and any changes I can make to help others.