How to Put a Chain on a Mountain Bike?

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Mountain bike chain

Bikes are pretty simple in their construction yet complex in their maintenance; that’s why we may not always know when or how to maintain them. Yet, changing your bike’s overworked chain is an excellent way to smoothen your ride and ensure your safety.

Growing up with a tremendous love for bikes, I’ve learned the ins and outs of those amazing exercise machines!

If you’re wondering “How to put a chain on a mountain bike?” keep on reading.

How to Put a Chain on a Mountain Bike?

Once you’ve gathered an idea about the process of changing a bike chain, it’s not too complicated. You should begin by checking the wear on your old chain and get a new compatible chain if it’s worn. 

Break the master link on the old one and then fix up the new chain through the derailleurs, cassette, and crankset. Join the links together, and you’re good to go.

In this section, I’ll give you a step-by-step guide on how to do it as smoothly as possible.

Step 1 – Check Compatibility
Step 2 – Secure Your Bike
Step 3 – Removing the Old Chain
Step 4 – Measuring the Chain’s Length
Step 5 – Check the Chain
Step 6 – Tension Check
Step 7 – Skipping Check
Step 8 – Stretch Check
Step 9 – Lubricating the Chain
Step 10 – Checking for Proper Maintenance

The Tools You’ll Need

There are a few essential tools that you’ll have to prepare to go through the process, which are as follows:

  • Chain wear gauge: Firstly, you should use the chain wear gauge to check the wear on your chain to make sure it needs replacement. 
  • Chain breaker: A chain breaker helps you remove links from the chain to adjust its length. You can also use it to attach or reattach chains.
  • Chain whip: The whip holds the cassette in place while removing the old chain and installing the new one.
  • Cassette locking tool: You’ll use the locking tool to remove and install the new cassette.
  • Allen wrenches: You’ll need the Allen wrenches to remove and install bolts and other components on the bike.
  • Pliers: Pliers will help you to hold the chain in place while working on it.
  • Cleaning supplies: Before attaching the new chain, you should make sure the drivetrain is thoroughly clean. This includes the various parts of the chain like chainrings, cassette, and derailleur. Use a degreaser, brush, and rag to clean all of these parts. We’ve got a full guide on the best chain degreasers for bikes.
  • Lubricant: Once you’ve cleaned the drivetrain, lubricate it to help the chain move smoothly and prevent rust.

Steps to Put a Chain on a Mountain Bike

Now that you know the tools, let’s look at the step-by-step guide to putting a chain on a mountain bike.

1. Check Compatibility

Mountain bike chain links

Before replacing your old chain, you should ensure the new one is compatible with your bike. Different chains suit various speeds and typically only suit particular drivetrains.

Generally speaking,10-speed, 9-speed chains and anything below will be compatible together, with some rare exceptions like Campagnolo.

However, if you’re getting a 10-speed Shimano, you’re in luck as it has a special mountain bike-specific design.

On the other hand, if you opt for 11-speed chains, there may be some wiggling if you crossover brands.

Finally, 12-speed and 13-speed drivetrains give you no cross-compatibility at all, so you should stick to the proprietary manufacturer and the groupset genre.

2. Secure Your Bike

Mountain bike flipped upside down resting on the seat and handlebars

Start by placing your bike on a rack and hanging it on the hooks. If you don’t have access to a rack, you can flip your bike upside down to rest it on the seat and handlebars.

It’s a helpful precaution to take a picture of the chain. Make sure that it shows how it feeds through the gear mechanism. Doing so helps you remember what the chain should look like after proper installation.

3. Removing the Old Chain

Using a chain breaker to push the link through the chain and remove it

If you use a chain wear indicator tool and find that it’s above 0.5%, it’s time to throw that chain away. To remove the old bike chain, you have to do the following:

  1. Shift the chain to the smallest chainring and the smallest cog on the cassette.
  2. Locate the master link on the chain as it’s the link you can easily disconnect without a chain breaker.
  3. Use pliers to press the side plates together to remove the master link.
  4. Once you remove the master link, you can take the chain off. You might need to wiggle it off the cassette and chainring, but it shouldn’t be too hard.
  5. You might need to clean the chain a little to make it budge if it’s too dirty or rusty. To do so, you can use some degreaser and then scrub it with a brush. 

4. Measuring the Chain’s Length

Start by determining the correct chain length you need to fit your bike—the proper length contributes to a smooth operation.

You have to take into account the number of gears on your bike and the size of the chainrings and cogs.

Count the number of teeth on the largest chainring and the largest cog on the cassette. Then, add those two numbers together, and add two additional links for the chain to overlap.

Make sure that you route the chain through the derailleur pulleys to ensure proper seating.

Note that if the chain is too long, it’ll cause sagging and the chain will rub against the derailleur cage. On the other hand, if it’s too short, it’ll cause damage to the drivetrain and make it difficult to change gears.

When joining the chain, make sure it’s secure, whether you’re using a master link or a chain tool. With the latter, make sure you push the pin in far enough to secure the connection.

5. Check the Chain

There are some checks you have to make to ensure everything’s up to par. If you find tension, skipping, or stretching in your chain, they’re all signs that it’s worn out and needs changing.

6. Tension Check

Mountain bike chain with lots of slack
Your chain should not have this much slack

Once you install the new chain, check its tension. It should be tight enough that there’s no slack, but not so tight that it puts pressure on the chainrings and derailleur.

A good rule of thumb is to pull the chain down at the midpoint between the chainring and cassette; there should be just enough slack.

You can also use a chain checker tool to double-check. The tool should fit between the chain and the chainring teeth but shouldn’t fit between the chain and chainstay.

7. Skipping Check

When switching gears, does your chain slip or jump between gears? If so, you might need to loosen or tighten it, depending on the chain length check.

8. Stretch Check

Chain stretching is a commonplace thing. To check for it, you should measure the distance between the 12 links on the chain. If it’s more than 12 1/16 inches, your chain is stretched and needs replacement.

If you find issues with all of the previous, you should remove your old chain and replace it with a new one.

9. Lubricating the Chain

Applying lube to mountain bike chain

Before you install the chain on the bike, make sure to lubricate it well. This extends the chain’s lifespan as well as lets the chain move seamlessly for easier pedaling. 

10. Checking for Proper Maintenance

Finally, before you put the new chain on the mountain bike, check the condition of other components.

Take a look at the cassette and chainrings to check for damage or signs of wearing out. If you find any, make sure to replace them before installing the new chain.

Otherwise, you’ll be shortening your chain’s lifespan as it’ll be coming in contact with worn-out components, putting more pressure and wear on it.

What’s the Difference Between a Mountain Bike Chain and a Road Bike Chain?

Not all bike chains are created equal. The differences between them have to do with the speed and riding conditions/terrains.

Manufacturers make mountain bike chains to suit heavier loads and to be able to shift up for mountainous terrain.

On the other hand, road bikes come with a design that suits shifting down, flat terrain, and high-speed sprints.

Then, there are hybrid bikes, which come with rim caliper brakes that are in direct contact with the frame which squeeze the rim to stop.

What Are the Standard Dimensions of a Bike Chain?

The distances between the links of a bike chain span ½ an inch. Moreover, the outer link is thicker than the inner one. The design of the inner one serves single-ring drivetrains and gives you a strong connection between the teeth on the chainring and the chain, alternating between narrow and wide chainring teeth.

Note that roller derailleur roller widths are almost the same for all speeds, be it 5-speed, 8-speed, or 9-speed chains and above. The difference lies in the width of the side plates.

Does Regular Removal for Degreasing Cause Damage?

If you don’t have a master link and you have to remove the chain completely to degrease it, there might be a risk of damage.

However, if your chain has cylindrical pins, the damage would be negligible. Most single-speed chains and some narrow chains have cylindrical pins.

You’re good to go about 10 times using the same pin each time. However, if your chain comes with profiled pins, you’ll have to get a replacement pin each time you take it off. Not to mention, replacement pins aren’t the smoothest to remove, so they do incur some damage to the side plates.


What if my chain is worn out and I don’t change it?

If your chain is stretched and needs replacement but you ignore it, it’ll cause damage to your bike’s drivetrain.

What is the proper chain length of a mountain bike?

The proper chain length for a mountain bike depends on the number of gears. Shift the chain to the largest chainring and the largest cog, add to links, and you’re good to go.

How do I put a chain on a mountain bike with gears?

First, thread the chain through the derailleur. After that, wrap it around the largest chainring and the largest cog.

Then, use a chain breaker to break it at any link and remove the excess links. Finally, join the chain using a chain pin or a quick link. Adjust the derailleur to ensure that the chain shifts smoothly.

Final Thoughts

In short, I hope this article gave you some guidance regarding how to determine whether your chain needs replacement and how to do it. 

It’s important to note that if you’re replacing the old chain due to wear, it’s likely that you’ll need to replace the cassette and chainrings too, so make sure to keep that in mind.

So, what are you waiting for? Grab your chain wear gauge and check if your bike chain needs replacement. And if it doesn’t, make sure you provide it with proper maintenance to extend its lifespan!

Photo of author


Paul Tuthill
Growing up in Scotland, Paul developed a love for the outdoors and a desire for adventure from an early age.