The Shimano Dura Ace 9100 11spd Chainset offers the perfect balance of low weight and rigidity, making it the choice for road racing's elite riders across the world. The Hollowtech II 11-Speed Dura-Ace R9100 Chainset offers the perfect balance of low weight and rigidity, making it the choice for road racing's elite riders across the world.The hollow outer chainring eliminates outer chain flex, hugely improving shift performance even under a high load, reduces weight and improves rigidity. The industry leading Hollowtech II 4 arm cold forged hollow crank arms increase rigidity, reduces weight and improve strength and the wide range of ratios and crank lengths available allows riders to find a chainset that is perfectly suited to their riding style.The Hollowtech II integrated bottom bracket design uses a wider bearing placement and larger axle diameter for increased stiffness and efficiency, and the bottom bracket seal design features a minimal bearing interface to offer incredibly smooth rolling and increased durability.The Shimano Dura Ace R9100 chainset is the perfect choice for anyone looking to upgrade their existing Hollowtech II drivetrain.Hollow outer chainringIndustry leading Hollowtech II 4 arm cold forged hollow crank armsTeeth developed to work only in conjunction with 11-speed chainsWide range of chainring ratios and crank arm lengths availableHollowtech II integrated bottom bracket designBottom bracket seal design has a minimal bearing interfaceWeight: 609 grams (50-34T  Shimano Dura Ace 9100 11spd Chainset Features  InterfaceWeight: 609 grams 50-34T   Hollowtech II integrated bottom bracket  conjunction with 11-speed chains