How to Change the Chain?
Considering the many components on a bicycle, the chain is one of the parts that wears out the most and needs to be replaced first, before it damages other components.
The first thing to consider when buying a new chain, which is the first step in answering the question of how to change a chain, is that the chain must be compatible with your number of gears (cassette). For example, keep in mind that a 10-speed compatible chain will only work with a 10-speed cassette.
You will need a few simple tools to change the chain. These are a chain tool and a chain link remover. Before installing the new chain, we obviously need to remove the old one. If your rear derailleur has a lockout lever, close it first, then shift the gear to the smallest sprocket on the cassette and the smallest chainring on the crankset. If you are using a Shimano chain, position the chain in the wrench and continue turning the lever until the pin comes out from the back. Be careful to do this on the bottom part of the chain. On Shimano chains, perform this operation on the middle link marked ‘HG’. If you are using an SRAM chain, the connecting link is darker than the others, and you will need pliers-like chain tool to remove it. Although some people manage to remove this link by hand, it is not easy even for experienced riders. Insert the pliers into the connecting link and squeeze. The link's lock will open as it moves inward.
After removing the chain, pay attention to how it passes over the cassette. You can take a photo to remind yourself when installing the new one. This ensures the chain is properly mounted from the cassette to the rear derailleur.
Now it's time to install the new chain. If you are using a Shimano chain, you will see markings on only one side of the chain. Remember that these markings should face outward. Start by passing the chain over the front derailleur and the smallest sprocket on the crankset. Then, gently turn the pedal to allow the chain to slide 5-10 cm down the crank. Then, pass it over the smallest sprocket on the cassette and through the rear derailleur. As I mentioned earlier, the rear derailleur part can be confusing. At this point, you may need the photo you took. So, take your time and make sure you follow the correct steps. Now you need to be on the smallest cog on both the chainring and the cassette, and we will mount the two ends of the chain together to form a straight line. Stretch the part coming from the rear derailleur a little to create some space between the crank and the cassette. This way, you will keep the two ends of the chain taut but still long enough to connect to each other. On Shimano chains, the intermediate links connect to each other as inner and outer parts. The outer parts are naturally wider than the inner parts. On SRAM chains, the intermediate link connects two inner parts to each other. If the chain is a few links too long, you should first remove the intermediate links and then connect the appropriate links to each other. To simplify this process for Shimano chains, secure both ends of the chain with a piece of wire. This allows you to work easily on the taut chain. Insert the intermediate link pin into place and secure it by turning the chain tool. Once the pin is fully seated, trim the excess protruding from the back using the chain tool. Then check if the chain moves smoothly with the new pin.
For SRAM chains, attach the parts of the intermediate link to both ends of the loose chain. Then, pass the two ends through each other and tighten them. This will seat the intermediate link in place. To check, squeeze the rear brake and press down on the pedal. This will ensure the pin is seated correctly. Similarly, turn the pedal to ensure the chain moves smoothly and freely. Reopen the locking lever (if present) on the rear derailleur from the first step. Finally, turn the pedal and check that the gear changes are normal. Try every gear combination. Also, remember that the chain should work properly on both the largest chainring and the largest cassette sprocket.
