Ultegra FC-R8000 Crankset
Shimano's Ultegra FC-R8000 Crankset represents true trickle down from Shimano's flagship Dura-Ace group not only visually, but in the technological features that make both cranksets light, stiff, and shift with precision. The new, aggressively angular lines increase stiffness, providing excellent power transfer. The chainrings and bolts were also redesigned to provide better chainstay clearance for shorter rear end bikes or road disc bikes with wider dropout spacing.
Shimano has the technical expertise and manufacturing prowess to create industry-leading shifting and stiffness to weight for the rings and crank arms, respectively. The latter property is owed to Shimano's Hollowtech II arm construction, a heavily guarded secret. Where other manufacturers drill the arms to reduce weight or create two sides and clam-shell them together, Shimano is able to forge the arms and still keep them hollow. As with the Dura-Ace 9100 series, Shimano adds some width to the R8000's arms and orients the spider to more efficiently transfer energy during important power phases throughout the pedal stroke. The asymmetric spider and chainring spacing allows Shimano to put two chainring bolts close to the wider arms, further adding rigidity to the rings for better shifting and power transfer.
As noted above, Shimano's excellent chainring engineering continues with the FC-R8000. We once heard a rumor that Shimano owns patents on every single chainring tooth's shape, pin, shift ramp, etc. We're not sure if this is true, but we do know that, compared to other rings we've used, Shimano rings in operation tend to run much quieter, wear at a much better rate, and offer more positive and quicker shifting.
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