Bike chain care and when to replace it

The chain is the fastest-wearing part of a bicycle drivetrain and the one whose maintenance is most often neglected. A well-cared-for chain can cover several thousand kilometres; a neglected one can start to stretch and deform in under half that, taking an expensive cassette and chainrings down with it.

How often to lubricate, and how

For ordinary commuting, lubricate every two to three hundred kilometres, and more often if you regularly ride in the rain or through standing water. Wipe the old oil and grit off the chain with a dry rag first. After applying lubricant, leave it a few minutes to work into the rollers, then wipe the excess off the outside — oil left on the surface simply collects dust and turns into grinding paste.

Knowing when to replace it

The usual method is a chain wear gauge, which tells you whether the chain has stretched beyond a safe limit. A chain left on too long has a lengthened pitch that chews through the cassette's tooth profile, and once the cassette has to be replaced alongside it the repair costs several times more.

Cleaning and storage

Before a long spell off the bike, clean the chain thoroughly and lubricate it, which greatly reduces the chance of surface rust while it sits. If you do not wipe the chain down after a wet ride, grit works its way between the rollers and the side plates — and it is those fine particles, rather than the water itself, that actually accelerate chain wear.