Ultegra R8000 will use redesigned derailleurs across the board, although they’ll thankfully retain compatibility with current levers.
Just as with Dura-Ace R9100, the new Ultegra RD-R8000 mechanical and RD-R8050 electronic rear derailleurs move to a Shadow configuration adapted from Shimano’s mountain bike components. The lower-profile parallelogram should help shield the mechanism from damage in a crash, while its longer length also provides more chain wrap around each cassette cog for reduced drivetrain wear and more consistent shift performance across the range.
Changes to the Ultegra Di2 front derailleur are mostly superficial, but the rear has undergone a much more thorough overhaul, including the Shadow low-profile parallelogram mechanism and a new Direct Mount attachment method. Photo: Shimano.
Also trickling down is the so-called Direct Mount mounting interface, which hangs the derailleur further back from the frame than before for improved shifting and greater chain wrap across the cassette range.
For now, a short aluminum link keeps both rear derailleurs compatible with frames built with standard hangers. Those should slowly start to go away as frame manufacturers begin to build specific hangers to suit, though, with the added benefits of a sturdier mounting platform and more clearance for faster wheel changes. Notably, BMC has already started to offer its latest Teammachine SLR01 with a Direct Mount hanger.
Whereas the latest Shimano Dura-Ace rear derailleur makes do with a single pulley cage length to handle cassette cogs up to 30T, the new Ultegra R8000 rear derailleurs will be offered in two: one to handle cogs up to 30T, and a slightly longer one to accommodate 34T sprockets. Photo: Shimano Australia.
To accommodate extra-wide cassette gear ratios, Shimano will offer the new Ultegra rear derailleurs in two cage lengths instead of the single one currently featured on Dura-Ace. The shorter SS version will handle cassette cogs up to 30T, while the longer GS variant will officially accommodate up to a 34T sprocket.
While changes to the Ultegra FD-R8050 Di2 electronic front derailleur are more cosmetic in nature, the mechanical version undergoes a more dramatic transformation. As with Dura-Ace, the new Ultegra R8000 front derailleur abandons a traditional lever arm in favor of the same spool-like assembly that was introduced last year. In addition to being lower in profile for better leg and tire clearance, the new mechanism directly incorporates a handy cable tension adjustment so inline adjusters are no longer needed. Leverage ratio refinements reduce the amount of hand effort required to shift, too.