The HollowTech II 12-speed Dura-Ace chainset offers the optimum balance of light weight and rigidity, making it the global choice for road racing's elite riders

Features

• Hollow outer chainring, giving vast improvements in rigidity and increased weight savings
• The hollow outer chainring has essentially removed outer chainring flex, hugely improving shift performance making it precise even under high load
• These industry leading HollowTech II 4 arm cold forged hollow crank arms have been evolved to increase rigidity, reduce weight, and improve strength
• The teeth have been developed to work only in conjunction with the 12-speed chains for improved contact providing more efficiency and improved power transfer
• There is a wide range of chainring ratios and crank arm lengths available enabling customisation for all riders and racing disciplines
• HollowTech II integrated bottom bracket design uses a wider bearing placement and larger axle diameter for increased stiffness and efficiency
• Bottom bracket seal design has a minimal bearing interface gives superbly smooth rolling and increased durability