Shimano dura ace r9100 11 speed groupsetthe jewel in shimanos crown the dura ace range does not need an introduction favoured by the majority of teams in the pro peloton the dura ace 11 speed groupset emulates its predecessor every component in this dura ace groupset has been re engineered for optimal weight savings alongside maximum energy output with minimal loss through friction or non compliant components the result is a beautiful marriage of stiffness with weight savings dura ace r910