Also see this thread in meta for more information on the differences between the and tags.

If your question is about, for example, keeping stuff on your bike in working order or in its best condition (such as your bike's drivetrain, brakes) it should have this tag. Questions about tires or paintjobs are borderline, depending on focus of the question.

This is one of the most popular kinds of question here, as you can see.

Example questions:

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