The chains marked with an asterisk (*) can remain on the drive for 1000 km, as the next chain would be one that has already run 500 km or 1000 km anyway. If all chains have run 1500 km, you can usually replace them again, but you should then measure the wear from time to time. There is often another 200-500 km per chain. The advantage is that the chainrings and cassette last a long time and wear evenly. If all the chains are worn, the chainrings, at least the middle and the small chainring, and the cassette are also due for replacement.
Thanks to BIKE reader Werner Mader, Wermelskirchen

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