How To Replace A Bike Chain

Your bikes chain is one of many moving components that should be regularly checked and replaced if worn.

Despite being made from hardened steel, the collection of links, pins and rollers can suffer intense wear and tear, especially if you cycle during winter when the roads become gritty.

It is vital that you replace your chain before it becomes overly worn, as this can cause serious damage to the expensive chainrings and cassette. To replace your bike chain, you’ll need the following tools:

  • A chain wear checker
  • A chain removal tool (Or a pair or quick link pliers)
  • And a new bike chain
  • The chain wear checker

A chain wear checker has the measurements 0.75% and 1%. If the wear is above 0.75%, the chain needs replacing. Anything on or above 1% and the cassette or freewheel will need replacing too.
How to remove a bike chain

Before you begin, make sure the chain is sitting at the lowest gear at the front and the highest gear at the rear. This gives us the least amount of tension on the chain.

Chain without a quick link

Place the chain into the lugs of the removal tool and slowly wind the lever. As it pushes through the links of the chain, release it and the chain will break apart. To completely remove, slowly feed the chain out of the componentry

Quick link chain

A cleaner quick link chain will be easier to remove, so we recommend cleaning your chain before you start. To remove the chain, place the pliers between the two links around the quick link and squeeze together, slowly feed the chain out of the componentry.
Give the cassette a good scrub

This is a great time to inspect your chainrings and cassette, paying close attention to ensure all the teeth are aligned and symmetrical. Once you’ve done this, spray some bike chain cleaner and give both components a good scrub.

Shop Chain Cleaner

Threading the new chain

Focusing on the smallest sprocket and chainring, thread the new chain through the front derailleur and turn the cranks, leaving a few inches of chain hanging loose. Next, loop it over the rear cassette and round the upper jockey wheel, before carefully threading it through the cage and around the lower wheel.

Size and cut your new chain

Sizing your new chain is next. With the chain placed around the smallest sprocket and chainring, pull both ends to meet below the chainstay. You’re looking for the longest possible length which still generates some movement in the derailleur arm.

If you’re adding in a quick link, remember to remove one extra link to make space for a new link. Make sure you are left with two inner links, one at either end. When you have the right length, using the chain tool split the chain.
Insert the pin and connect the new chain

Locate the sharp end of the pin that came with your new chain. Next slot together both ends of the chain and insert the connector links by hand

If you’re not using a quick link, line both the inner and outer links and push the pointy end of the pin through the chain. Using the removal too, wind through the rest of the pin and ensure the pointy end of the pin is completely through the chain. Using a set of pliers, break off this part of the pin.

Maintaining a healthy bike chain

Regularly cleaning and lubing your bike chain is the best way to prolong its life. We stock a great range of bike maintenance products, including bike chain lube, bike grease and brake oil to ensure all your bikes moving parts are in tip-top condition.

Cleaning the chain on your bike doesn’t take very long and is relatively inexpensive, but the impact it has on performance is huge. We recommend using both a chain cleaner and lubricant for the best results - both of which can be found at Halfords.