ROTOR Bike Components - Now you can assemble your Shimano® Dura-Ace R9100 or Shimano® Ultegra R8000 cranks with the new ROTOR Q RINGS BCD110X4 and enjoy all the advantages of oval chainrings. #
how to mount large and small Oval chainring to Ultegra 6800, Dura ace 9000 - YouTube
ROTOR Bike Components - Now you can assemble your Shimano® Dura-Ace R9100 or Shimano® Ultegra R8000 cranks (covers also available) with the new ROTOR Q RINGS BCD110X4 and enjoy all the advantages