How to Fix a Rusted Bike Chain
It sat outside all winter. It feels the way it looks.
Surface rust on a chain can be cleaned off. Stiff links can usually be freed. Pitted, stretched chains should be replaced, because a worn chain wears the cassette and chainrings with it.
Step by Step
- 1
Check the wear first
Use a chain-checker tool. If it is stretched past the limit, replace the chain and skip the rescue.
- 2
Soak the stiff links
Spray penetrant on each stiff link and flex it side to side and back and forth until it moves freely.
- 3
Clean it
Wipe or degrease the chain to remove the loosened rust and the penetrant. Penetrant is not chain lube.
- 4
Lube it properly
Apply a chain lube to each roller, let it soak in, then wipe the outside of the chain.
No heat. It ruins a chain’s temper and does nothing for rust.
- Keep penetrant and chain lube off disc-brake rotors and rim braking surfaces.
Which Penetrant, and Why
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Common Mistakes
Leaving penetrant on as the chain lube.
Saving a stretched chain and wearing out the cassette.
Related
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