How To Fit A Chain On A Mountain Bike – Step by Step Guide By Experts

If your mountain bike chain brakes fall off, you will need to buy a replacement for it as soon as possible. If you just want to repair a broken one you can purchase a chain to replace the part that is broken, or a new one completely. It is also important to understand and note that bike chains are also subject to wear and tear.

What Is Chain Wear?

Chain wear is normally known as 'chain stretch' this is because the pitch grows as it wears, it is the most common type of chain wear. The wear comes from the brushings wearing the pin chains. Over a period of time the diameter of the brushings increases. Commonly chain wear is defined as 0.5in of growth. The second type of wear is 'slop' which can't be measured, but is gaged by poor shifting. Bike Radar has an in-depth article on chain wear signs.

Why Is Chain Wear Important? Eventually, it will lead to poor shifting or even snap off. If it is left undetected in the long run it can cost you a lot of money to correct. This is because a new chain at a 0.5in pitch will sit deep into the cog. As the pitch increases, the chain will roll farther up on the tooth, this will increase cog wear. Possibly, this may need replacing in future which will also increase your bike maintenance bills.

To Replace A Chain:

  • Turn the pedal slowly until the chain passes through the spokes and releases itself. Or remove your hands if it becomes stuck.
  • Secure the chain's teeth into a chain tool, turn the tool's handle until the pin pushes out then remove it.
  • Turn the bike over and elevate so the wheels are off the ground. You can use props to ensure your bike is standing upright securely. Once in this position thread the chain to the rear derailleur.
  • To help you achieve a good fit for your chain do keep in mind the derailleur. If the derailleur has a shift mechanism move to the highest and lowest gears on the front derailleur to get a good fit.
  • Pull the chain through the rear derailleur. Ensure that you thread it so there are a smooth transition and fit. Thread the 'female' end of the chain through the top and bottom pulley all the while ensuring that it is smoothly placed.
  • To thread the chain the chain through the top and bottom pulley all and while ensuring that it is smoothly placed.
  • To thread the chain through the cassettes, pull it through the smallest sprockets of the cassette.
  • Pull the chain thorough the front derailleur, and turn the rear wheel to pull enough chain through to meet and fix the front derailleur. Line up the chain with the front sprockets.
  • Finally, connect the female and male sections of the chain, hook the pin from one end to the other. Rest the chain in the groove of the chain tool to secure it. 

Replacing A Chain That Has Slipped:

Replacing a chain that has slipped is easier than fitting a completely new one. As the chain will already be attached to both of the front and rear derailleurs, all you will need to do is ensure the chain is secured into the sprockets.


First, take a close inspection and identify where the chain has jammed. Release the chain from the jam by loosening the front wheel so that you can clear the jam, by pulling the chain out. To do this push the arm of the front derailleur forward, ensure there is enough slack to thread the chain back into the sprockets. Replace the arm of the derailleur and tighten back into place. Turn the pedals until the chain slips into the gear it was in before the slip.

Things To Note:

Chain replacement and repair is easy however if you do not feel confident to do this don't attempt it yourself. Take your bike to your nearest bike specialist shop and allow them to fully inspect and repair your chain. If your chain is pretty worn you may need to replace your cassette as well. A great article on this is from Bike Radar Ensure that you buy the correct chain for your bike, there are three main types:

1. A chain joined by special replacement pin, a special pin is inserted that takes the place of a stock pin.

2. A chain joined by a special connecting link. Joined by a special link that has two outer plates with protruding pins, that is inserted into the chain rollers, aligned to fit together and then snapped tight by pushing on the pedals.

3. A chain joined by any pin, the traditional method of joining a chain, by pushing any pin out far enough to be able to flex the chain to separate the ends. The Clean Machine is a great place to start to understand the differences between the three. Check that your chain is not bent before you replace it, a common mistake is to replace a chain that is just bent. If you find it is pushing it into shape.

Click Here to Leave a Comment Below 0 comments