The basics

Why

On every ride, dust mixes with the chain oil and settles on everything it touches: between the cassette sprockets, on the chainring teeth and around the derailleur jockey wheels. That black paste wears the parts and gets in the way of shifting. A clean chain on a dirty cassette is dirty again within one turn.

When to do it

• When the cassette and jockey wheels are black and sticky, even after wiping the chain.
• After a ride in mud or on wet, greasy roads.
• Before fitting a new chain, so it doesn't get dirty straight away.
• The rest of the time, cleaning and lubing the chain is enough.

Where the dirt builds up

The places to brush are the gaps between the cassette sprockets (1), the rear derailleur jockey wheels and their cage (2), the chainring teeth (3), and of course the chain (4).

Steps

1. Get the bike ready

If practical, take the rear wheel out: the cassette is much easier to brush. Put the bike in a work stand or against a wall, drive side facing you.

2. Start with the dirtiest part: the chain

Park Tool advises starting with the chain and drivetrain, the dirtiest parts, so you don't dirty the rest of the bike afterwards. Apply degreaser to the chain, let it work for a few minutes, then brush it while backpedalling.

3. Brush the cassette

Lay the wheel sprockets facing the ground: the degreaser then drips outwards and not into the hub bearings. Apply degreaser, let it work, then run the brush between each sprocket. A strip of rag pulled back and forth between two sprockets, like shining a shoe, takes off the rest.

4. Chainrings and jockey wheels

Brush the chainring teeth, on both sides. On the jockey wheels, dirt often forms a hard ring: scrape it off with the brush, or a small piece of wood, while turning the wheel.

5. Rinse gently

Rinse with clean water, at low pressure: a gentle spray, or a sponge and bucket. Then wash the rest of the bike with warm water and mild cleaner, from top to bottom.

6. Dry it, especially the chain

Wipe the chain with a clean, dry rag. A chain oiled while still wet keeps the water in its rollers. The rest of the bike can air dry. With compressed air, don't blast the bearings directly.

7. Re-lube

Refit the wheel, then put one drop of lube on each roller of the chain and wipe off the excess: see Clean and lube your chain. Add a drop on the jockey wheel axles and the derailleur pivots.

Check it's done right

• You can see metal between the cassette sprockets.
• The jockey wheels turn freely, without a ring of dirt.
• The chain feels dry on the outside and backpedalling is quiet.
• The brakes work normally: test them at low speed before riding off.

Common mistakes

• Not drying the chain before oiling it.
• Letting degreaser run into the hub, with the wheel sprockets up.
• Getting degreaser or oil on the rotors.
• Reaching for the powerful jet to go faster.

What next

Log the clean in your logbook. It's also a good moment to measure chain wear: a clean chain is the easiest to read.

Sources

This guide was checked against the following documents:

• Park Tool, How to Wash a Bicycle (cleaning order, cassette, bearings, drying, lubing)
• Decathlon Conseil Sport, looking after your bike (pressure washers, degreasing, drying), in French

Values vary between models: your part's manual always takes precedence.