Check for wear
Use a wear indicator. If the 0.75 side fits, the chain is worn but the cassette is often still good.
If side 1.0 fits, plan to replace the cassette as well.
How to replace a bicycle chain?
Replacing a bike chain may seem like something only real mechanics can do, but it's actually much easier than it looks. With a few explanations, the right tools, and a little patience, you can easily do it yourself. Better yet, replacing your chain in time will make your bike quieter and smoother, while preventing premature wear and tear on much more expensive components.
In this article, we explain step by step how to replace a bike chain, what to look out for, and what mistakes to avoid. No complicated jargon, just clear explanations, practical insights, and concrete advice. After reading this, you'll know exactly what to do and can get back on the road with confidence.
Written by: Hanna Stevens | December 24, 2025 | Reading time: 5 minutes
More about the author: Hanna Stevens
Hanna is an avid cyclist who loves exploring new routes and sharing her experiences to inspire others to get on their bikes more often.
Key findings
- Replacing the chain in time saves money and improves the quality of gear shifting.
- With the right tools, anyone can do it themselves.
- Inspection and maintenance after assembly are just as important as the assembly itself.
Table of contents
When should you replace a bike chain?
What tools do you need to replace a bicycle chain?
How to determine the correct length of a new bicycle chain?
How to properly install a new bike chain?
How to securely lock a bicycle chain?
What should you pay attention to after replacing the chain?
When should you replace a bike chain?
You should replace your chain as soon as it shows visible wear, before other components are damaged. If you opt for a belt drive, maintenance and replacement are much less frequent.
How to check the wear on your chain?
The most reliable method is to use a chain wear gauge (also called a wear indicator). This small tool is placed between the chain links.
How to read the wear indicator:
- The gauge won't fit? The chain is still in good condition.
- Does the 0.75 side fit? The chain is worn and needs to be replaced. In general, the cassette is still in good condition.
- Does side 1.0 fit? The chain is badly worn. It is very likely that the cassette will also need to be replaced.
For 11- and 12-speed chains, it is advisable to replace the chain as soon as it shows 0.5% wear in order to avoid additional costs.
No channel controller handy?
You can also perform this simple test:
- Place the chain on the large front sprocket.
- Pull it gently forward.
- If you can pull it far away from the plate, the chain is worn out.
What tools do you need to replace a bicycle chain?
With the right equipment, this operation becomes simpler and safer.
| Tool | Usefulness |
|---|---|
| New bike chain | Must match the number of gears |
| Chain drift | To remove links |
| Chain pliers | For a quick link |
| Chain hook or old spoke | Keeps the chain in place |
| Cloth and degreaser | To clean the entire unit |
| Chain oil or wax | For lubrication after assembly |
Pay close attention to the number of gears (9, 10, 11, or 12). An incorrect chain will not fit properly and will result in poor gear shifting.
Step 1: Remove tension from the chain
- Shift gears in the front and rear to the smallest sprocket.
- The derailleur is thus subjected to minimal tension.
Step 2: What type of clasp does your chain have?
With quick link:
- Recognizable by a link that looks different
- Place the chain pliers on the link.
- Tighten firmly until it comes off.
Without quick link:
- Use a chain breaker
- Push the pin out of any link
- The chain then separates
Step 3: Remove the chain
- Carefully remove the chain from the sprockets.
- Ensure that it does not touch the frame.
Now is the ideal time to clean the cassette, derailleur pulleys, and chainrings. A new chain mounted on a dirty drivetrain will wear out more quickly.
How to determine the correct length of a new bicycle chain?
A new chain is always too long and needs to be adjusted.
Method A: Comparison with the old chain
The simplest method.
- Place the old and new chains side by side.
- Count the number of links
- Adjust the new chain to the same length.
Caution: the old chain is slightly "stretched." Align them link by link.
Method B: The great-grand method
More accurate.
- Place the chain on the largest front and rear sprockets.
- Without going through the rear derailleur
- Pull the chain straight
- Add two additional links
On MTB , a few extra links may be necessary.
How to properly install a new bike chain?
Follow the correct path and be careful with the derailleur.
- On the smallest front tray
- On the smallest rear sprocket
- Along the upper pulley of the derailleur
- Through the derailleur housing (without touching the metal plate)
- Along the lower roller
Use a chain hook to hold the ends together: this makes the job much easier.
How to securely lock a bicycle chain?
Option A: With a Quick Link
- Place both halves in the inner links.
- Follow the arrows and direction of rotation.
- Fit them together
- Use chain pliers or press firmly on the pedals.
Option B: With a break axis
- Assemble the inner and outer links.
- Insert the breakaway pin
- Push it in with the chain driver.
- Break off the protruding part.
- Check that the link moves freely.
What should you pay attention to after replacing the chain?
A final check prevents many problems while driving.
- Turn the pedals: is everything working smoothly?
- Shift through all the gears
- Check the grandparent and grandchild positions
- Lightly lubricate the chain.
If the chain jumps off during your first ride, it is likely that the cassette is too worn and also needs to be replaced.
Replacing your bike chain
Simple maintenance to save money and improve fluidity
The right equipment
Equip yourself with a chain tool, a link pliers (Quick Link), and a chain suitable for your number of gears.
Please note: an 11-speed chain will not work on a 10-speed cassette.
Remove the old one
Shift to the smallest sprocket to release the tension. Use the pliers to open the quick link or chain tool.
Clean your derailleur pulleys before installing the new chain.
The right length
Compare the new chain with the old one link by link or use the "Grand-Grand + 2 links" method.
Don't be fooled by the total length; the old chain has stretched over time.
Installation & Routing
Pass the chain through the rear derailleur. Make sure it does not rub against the metal plate on the cage.
Observe the direction of rotation if arrows are present on the links.
Testing & Lubrication
Close the Quick Link, lubricate lightly, and shift through all the gears to check that nothing jumps.
If the chain jumps off the new sprockets, your cassette is too worn.
FAQ
How often should a bicycle chain be replaced?
On average between 2,000 and 4,000 km, depending on maintenance and driving style.
Can I continue to ride with a worn chain?
Yes, but this causes additional wear on the cassette and chainrings.
Is a Quick Link preferable to a breakaway pin?
The Quick Link is easier to assemble and disassemble.
Should a new chain be lubricated?
Yes. The factory grease is sufficient initially, but additional lubrication will extend the service life.
Can I use any chain on any bike?
No. The number of gears must always match.