Even if a derailleur chain is still fully functional, it no longer matches the sprockets exactly once it reaches a certain wear size. If the chain is not replaced with a new one now, the sprockets and chainrings will wear in prematurely and then also have to be replaced when the chain is changed. With the Rohloff CALIBER 2 it is possible to quickly and reliably determine exactly the right time to change the chain and thus avoid unnecessary costs.