How to Replace a Bike Chain

Attacked by a tree? Jumped by a rock? Or is that poor bike chain just rusted and sad? There are plenty of ways a bike chain can jump off the pulley and keep you from using your bike, but it's pretty easy to put it back on if you don't mind a little oil on your hands. Here are some steps to give your bike a new ride.

Instructions

Difficulty: Moderate

Remove the Old Chain

1. Lean bike on a wall or place in a repair stand.
2. Use a link removal tool to place the chain in the channel section opposite the small crank.
3. Position the chain in the tool so that the tool's pin matches up with a pin in one of the chain's links.
4. Turn the tool's small screw crank so that it begins to push out the pin in the chain.
5. Push out the pin, unscrew the tool and take the chain out of the channel. The chain should separate.
6. Unthread the chain from the gears and set aside.

Install the New Chain

7. Thread the new chain through the gears. Be sure to run it the proper way through the derailleur, through the mechanism that shifts the front gears, around the rear of the bottom pulley and over the front of the top pulley.
8. Thread the other end of the chain through the front derailleur and over the front sprockets. (The front sprockets are the front gears, near the pedals.) The chain should pass through the "cage" of the front derailleur - the rectangular metal section that hangs over the front sprockets.
9. When the chain is threaded over the front and back gears, place the two ends together in the link removal tool.
10. The new chain should have a pin already pushed partway out. If it does not, push one end of the new chain in the link tool and press the pin most of the way out.
11. Slip the links together, flip the tool over, and turn the tool's crank to press the pin back in. Turn eight to ten times, or until the pin seals the links together and is flush on either side of the chain. The pin should not stick out on either side.
12. Lubricate the new chain.

Tips & Warnings

• Shifting into the smallest rear cog before starting gives you more slack chain to work with.
• Some chains have "master" links that can be opened by hand without a link removal tool.
• If the chain slaps the frame while you're riding, or appears to sag, it's too long. Remove one link with the tool.
• Dry lubricants, paraffin and some powdered chain treatments may have to be applied prior to installing the chain.
• Shimano chains have a special pin that you need to use to install or reinstall their chains. They also require a chain tool that is compatible with this special pin. Ask your bike shop for more information.