Shimano's 11 speed cranksets utilize a proprietary 4-arm bolt circle diameter that is asymmetric.Though there are aftermarket options for replacement or changing tooth count, premier level Shimano shifting requires the patented tooth design, pick-ups, and ramps of the 4-arm Hollowglide large chainring. This lightweight construction is inherently stiff, which only gets amplified when bolted to the integrated spider of the Hollowtech II drive side crank arm. Stiffness far exceeds the load of mechanical drivetrains, as the rings were designed for the power of the Di2 electronic front derailleur.

Available in several variations based on tooth count and small ring combination, the FC-6800 Outer Chainring is strictly available in the Ultegra grey color. The rings will work with 11-speed Dura-Ace and 105 4-arm asymmetrical crank arms, but won't color match. If you are fortunate enough to put enough miles on your Ultegra 6800 to have worn down the large chainring, or are just changing ring combinations, stay with Shimano and get the genuine Ultegra chainring for your 6800 crankset.