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Equipment > Components > Cranksets > Road


With the R8100-series Shimano drives their Ultegra-level components to 12-Speed, in conjunction with a decisive move to Di2-only equipped drivetrains. The efficiency and reliability of the electronic Di2 shifting system has been well proven, and this new generation brings many changes, including wireless communication from the shifters, which makes integrated cockpit set-ups much simpler, while also an increase in shift speed from the already lightning fast response of the previous generation. Yet the crux of any drivetrain is the crankset, and the design of the Ultegra FC-R8100 Crankset has also been improved, building off the incredible stiffness the line has been known for, but making changes to the construction and materials. The crankset delivers the power, drives the chain, and handles the shifting power of the Di2 front derailleur with ease no matter what combination you shift to or from. Ultegra has always represented the serious enthusiast and everyday cyclist who prefer value and steady excellence. it shares technology and design with the Dura-Ace version, at much more attainable price.

While much of the R8100 Crankset carries a construction process and resemblance to R8000 offering it replaces, a more detailed examination which shows a new version of the spider-arm design that has achieved an optimal balance of stiffness, strength, weight and rotational performance. This change also moves away from asymmetric arm spider design, and has more positive impact on the Power Meter version, as well as the striking visual presentation, which is more muscular and geometric. The proven Hollowtech crankarm design keeps the unit as light as possible, while producing the stiffest crank and chainring interface available, and the familiar 24mm Hollowtech II spindle integrates the bottom bracket axle with the right crankarm for more stiffness and weight savings to achieve a high-dimensional balance. The rigidity of the crankset ensures pedaling efficiency throughout the pedaling cycle. The two-piece Hollowglide large chainring structure cuts weight yet maintains strength and optimal for better power transfer and quicker, more precise front shifting, while crucially being able to handle the power of the Di2 front derailleur under any chain angle or gearing combination.

The Ultegra R8100 crankset is now available in a 160mm arm length, reflecting the generational change to higher pedaling cadence and advanced bike fit systems that have demonstrated that shorter cranks offer the same or similar rider power output, greater overall efficiency in most cases, and also reflect the desire for greater ground clearance. With 160, 165, 170, 172.5 and 175 mm lengths available, the ideal option for you is here. With the addition of a 12th cog to the cassette, shifting has only gotten faster and more precise, if more technically challenging. Faster cadences yield faster shifts, and the Di2 only R8100-series components maximize this experience with stunningly quick and dead-perfect accuracy. Shimano offers the R8100 crankset in a the most popular 50-34T set-up, along with 52-36T combination. Ultegra 12-speed brings two cassettes to the table, in 11-30, and 11-34 tooth options. The gearing combinations and cog steps offer great efficiency, a must for all higher cadence riders, most ideally those who do a lot of climbing. Many pro cyclists now use these wider cassette gearing ranges in the high mountains for the same reason, as efficiency within a rider's optimal power output range is critical to maintaining speed, answering attacks, and spinning away from those who can't hold the pace. You can have the same advantages, applied in the way you enjoy cycling.

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  • Updated, higher performing 12-speed Ultegra crankset that is more efficient and stiffer than ever before while maintaining impressive value
  • Drives two vital functions: transferring your pedaling effort into the drivetrain; and ensuring the fastest, most precise front shifting available
  • New driveside arm and spider design, with new 110mm BCD that further optimizes the Hollowglide 2-piece outer chainring stiffness
  • Hollowtech crankarms and spider, as well as 24mm Hollowtech II crank spindle for optimal power transfer
  • Shimano's BB-R8100 threaded external cup bottom bracket, or the SM-BB72-41B Press Fit version are the Ultegra bottom bracket options (Sold separately due to the frame specific nature of bottom bracket shells)
  • Q-Factor: 148mm
  • Chainline: 44.5mm
  • BCD: 110mm (specific design, and not compatible with 11 or 10 speed chainrings)
  • Arm lengths: 160, 165, 170, 172.5, 175 mm
  • Chainring combinations: 52/36T, 50-34T
  • Weight: 700 grams (50-34T, 170mm, listed)
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