"Upper to lower pulley-axle: 55 mm. Reiterating the concept of an integrated project, the Centaur groupset presents three rear derailleur models: short cage, medium cage and long cage to impart the greatest functionality depending on the crankset/sprocket set combination used. The short cage derailleur is recommended for use with a double / compact crankset and 13-26 cluster or smaller. The medium cage derailleur is recommended for use with a double / compact crankset and 13-29 cluster or smaller or with a triple crankset and 13-26 cluster or smaller. The long cage derailleur is recommended for use with a triple crankset and 13-29 cluster or smaller."

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