How to Clean a Bike Chain Properly

A chain is the fastest-wearing part on a bike and the one most exposed to everything the road throws at it. It is also, structurally, a long series of small plain bearings: each pin turns inside a bushing under load, thousands of times a mile. Grit that gets in there does not just make noise — it grinds the pins down and lengthens the chain, and a worn chain then wears the sprockets it runs on.

Cleaning is therefore not cosmetic. It is the difference between replacing a chain and replacing a chain, cassette and chainrings.

How often

Cleaning on the bike

This is what you will do ninety per cent of the time. It takes about ten minutes and does not require breaking the chain.

On-bike chain clean

1. 1

   Protect the brakes

   On disc brakes, remove the wheel or bag the rotor. Degreaser on a rotor or pads costs you a set of pads — see cleaning brake rotors.

2. 2

   Shift to the largest chainring and a middle sprocket

   This straightens the chain and gives you the best access.

3. 3

   Apply degreaser

   Either into a chain-cleaning tool clipped over the lower run, or onto a stiff brush. Backpedal thirty or forty revolutions.

4. 4

   Scrub the side plates and rollers

   A stiff brush along the top, bottom and both sides. Pay attention to the rollers themselves rather than just the shiny outer plates.

5. 5

   Do the jockey wheels

   The two small pulleys on the rear derailleur collect a black paste that is mostly worn chain. Clean them with a rag corner or an old toothbrush.

6. 6

   Rinse minimally

   A light spray or a wet rag. Never a pressure washer — it drives water and grit straight into the bearings.

7. 7

   Dry it completely

   Backpedal through a dry rag until the rag stops coming away grey. A wet chain flash-rusts within hours.

Removing the chain to clean it

Taking the chain off and shaking it in a bottle of degreaser gets it cleaner than any on-bike method. It also means repeatedly breaking and rejoining the chain, and a quick link has a limited number of cycles in it. It is worth doing occasionally, not routinely.

• Only practical if your chain has a quick link. Removing a pinned chain with a chain tool each time weakens it — the method is in removing a bike chain.
• Shake the chain in a sealed bottle with degreaser for a minute, then repeat with clean degreaser until it runs clear.
• Rinse, then dry thoroughly. A hair dryer or an hour on a radiator is not overkill.
• Re-lube generously before refitting, because you have stripped everything including what was inside the rollers.
• Many quick links are single-use. Check the maker's guidance and keep spares.

Re-lubing correctly

This is where most people undo their own work. The job of lube is to sit between the pin and the bushing inside each link. Any lube on the outside of the chain does nothing useful and actively attracts dust, which is why a shiny wet-looking chain is usually a badly maintained one.

While you are there

A chain clean is a natural moment to check two other things. First, chain wear — a worn chain should be replaced before it damages the cassette, and replacing a bike chain covers sizing the new one. Second, the cassette itself, which collects the same grime between its cogs; cleaning a bike cassette deals with that.