Chain

As the chain engages and pulls against the teeth of the cogs and rings, the bushings between the plates become worn. Play develops between the links until the distance between them is so great they no longer mesh evenly with the teeth. The drivetrain becomes clattery and shifting is balky or unpredictable. You can lengthen the life of your chain with regular cleaning and lubing; rather than recommend a time interval, we like the basic rule that your chain should never be dry or be wet enough to have anything stick to it. But even a well-cared-for chain will wear out, usually between 1,000 and 2,500 miles. Check your chain monthly with a Park Tool Chain Checker or by having Velo take a look. Ridden too long, a worn chain can in turn disfigure the teeth of the cassette and chainrings; if this happens, you have to replace those as well as the chain.

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