No matter how inexpensive or expensive a bike is, the day will come when its chain needs to be repaired or replaced. The structure of a mountain bike can be more complex than that of a normal one, but the process of changing the chain is similar. With the right tools and a little patience, your bike will have a new chain in no time.
Method 1 of 3: Extract the chain
Step 1. Secure the bike
The kickstand is unlikely to be sufficient for you to get a good look at a bike without it falling over. A bracket with hooks that you can hang the bike from will work best, but you can also turn the bike upside down so it rests on the seat and handlebars.
- Checking the chain with the bicycle wheels pointing up will make it easier for you to check and work on it.
- If you don't have a stand, you can simply prop the bike upright against the wall.
Step 2. Take a photo of the chain
To make the reinstallation process easier, you should take a photo of the chain so that you can refer to it later. Make sure the photo shows the chain going through the gear mechanism.
Step 3. Check for a hitch link
This item is a special link in the bicycle chain that has a pin or slot configuration that will allow you to easily remove the chain from the bicycle. Two popular types of hitch links are Connex and SRAM Powerlink. Know where the hitch link is located in advance to facilitate chain replacement.
- The hitch link for a bicycle must be specific to the size and brand of the chain.
- If your bike doesn't have a hitch link, you can install one yourself or at a local bike store. This installation is usually inexpensive and costs around $ 15 in most cases.
- If your bike does not have a hitch link and you prefer not to have one installed, you can request a chain cutter to remove it. This is an inexpensive and essential piece of equipment.
Step 4. Attach the chain
This procedure is especially important if you have a hitch link. Removing a hitch link that fits over chain ring teeth or a gear can be very difficult. It is easiest to position the hitch link so that it is suspended midway between the cranks and the rear wheel.
If you are using a chain cutter, you can still benefit from proper chain placement. Some parts of the chain will be dirtier or more worn than others. A clear segment of chain placed midway between the wheels will be easier to remove with a chain cutter
Step 5. Remove the chain
Now that the chain is in position, you can remove it. If you have a hitch link, you must use specific pliers or your hands to squeeze both ends of the link inward so that the pin comes out of its slot and the link separates, freeing the chain. If you are going to use a chain cutter:
- Set the chain tool over the link you are trying to remove so that it lines up with one of the round holes on either side of the link.
- Screw the chain cutter so that it goes through the hole. In this way, you are going to push the pin that holds said link together. Try not to push the pin all the way out of the link, as this will make it more difficult (and in some cases impossible) to assemble the link into the chain.
- Often times, a shock or snap is felt when the pin comes off the link. This is considered a good indicator that the link has disconnected.
- Some chain breakers are only designed for links of a certain size, while others can be used on chains of different sizes. Consult the instructions of the chain cutter before using it.
Method 2 of 3: Attach the new string
Step 1. Avoid using faulty chains as replacements
Chains generally fail because they have reached their limit or have been put under too much tension. Replacing a faulty chain on a bicycle could result in an even more serious failure down the road. To avoid injuring yourself or damaging your mountain bike, you should buy a new chain instead of reusing an old one.
You can find chains at your local bike store or, in some cases, at a hardware store
Step 2. Measure the replacement chain
It is important that you only use the type of chain designed for your bike. For example, you should use an 11-speed chain on an 11-speed bike. Hold the old chain so that it hangs freely and do the same with the new chain at its side.
- Count the number of links if the new chain is longer than the old one. This will be the number of links you need to remove.
- If the chain has broken and it is not reliable to measure the new chain, you can remove the links after inserting the chain into the bike's drivetrain.
Step 3. Insert the chain into the gear mechanism
If you have a more complex mountain bike, you may have to refer to the photo you took to verify how the old chain goes through the gear mechanism to do it correctly. Simple mechanisms can be more intuitive. Pass the chain through the entire drive train until both ends end at the lower midpoint between the wheels.
You should place the ends of the chain at the lower midpoint between the wheels to make it more accessible and allow gravity to keep it on the bike until you can secure it
Step 4. Remove the extra links from the chain, if necessary
If the chain is loose, you will need to remove some links. This will probably be the case if you failed to measure the chain. Put the bike in its lowest gear and then use the chain cutter to remove the links one by one and shorten the chain until it is taut on the transmission.
- When removing the extra links, you should prevent the pin from bursting by keeping them completely free from the link. This procedure will make it difficult to reconnect the link if you shorten too much.
- To improve the handling of the bike, you will need the chain to be taut between the wheels in the lowest gear.
Step 5. Attach the loose ends of the chain
With a hitch link, all you need to do is slide the link pin into its slot to complete the connection. If you removed the chain with a chain breaker, you will need to reattach the split link by lining up its halves and using pliers to force the pin through the hole to complete the connection.
You should feel a click or shock as the hitch link pin slides into place. You can also pull the chain on both sides of the link to securely install the hitch link pin in place
Step 6. Test the chain
Put the bike back on the stand and move the pedals with your hands to pass the chain through the drivetrain. The chain should move smoothly. If you find stiff links, this is often due to a loose pin that can be repaired by reattaching the pin with the chain cutter and pliers.
- Sit on the seat to go through the suspension and rock up and down several times to test the length of the chain.
- To protect the chain from the elements and help it run smoothly in the drivetrain, you should lubricate it with a suitable bicycle chain lubricant.
Method 3 of 3: Detect Chain Wear
Step 1. Use a wear indicator to evaluate the chain for better results
You can get a wear indicator at your local bike store or even a hardware store. You will have to connect the indicator between the links of the chain and follow the instructions to interpret its reading.
- Most wear indicators have a label that sets the values for a chain with or without wear. If your indicator does not have this detail, you should check the box it came in to find these values.
- If you don't have a wear indicator, you can do a manual check of the chain. Use moderate pressure to lift a section of chain off the chainring with your fingers. A small gap should form between the chain and the chainring. If you can see clearly through the gap between three or four teeth, then the chain is worn.
Step 2. Try joining the ends of the chain to test for wear as a simpler alternative
If you can't check the chain with a wear indicator or perform a physical gap check, or if the chain is already off the bike, you can also check for wear by trying to touch the ends of the chain. Lay the chain on a clean surface so that the holes are facing up and down. Later:
- Try to bring the ends of the chain together while keeping the holes up and down. Over time, the chains bend from the action of the gearshift.
- Take into account the amount of lateral flex in the chain. A worn chain will exhibit great flex. Newer chains resist contact and only bow slightly.
Step 3. Familiarize yourself with the transmission
This element is the piece that transfers the energy that you apply on the pedals through the chain to the gears to move the wheels. You should pay special attention to how the chain goes through the gears. Knowing how the chain fits into the mechanism will make it easier for you to replace it.