Dura ace moves to the next generation tested in competition and taken to victory by pro riders in all conditions including the 2012 tour de france team sky cutting edge technology for the ultimate in control and confidence with a unique four arm spider and hollowtech ii construction putting strength just where its needed the fc 9000 chainset sets new standards for stiffness and low weight key features new 4 arm design for same stiffness with lighter weight 11 speed compatible for