"Ultra-Drive™ chainrings - requires b.b. with 111 mm axle. The Centaur 10s crankset has the same technical innovations as the Record and Chorus groupsets in terms of the ultra-drive geometry of the chainrings. In the three sections of the chainring there are six pins and relative grooves that make it easier for the chain to move up onto the larger chainring. On the other hand, at two set points a special configuration of the chainring teeth makes it easier for the chain to drop down onto the smaller chainring."

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