Shimano Ultegra R8000 Medium Box Rear Derailleur

Product Information

For me, the biggest difference of R8000 over 6800 is the shape of the brake lever. The curve for your index finger is more pronounced and if, like me, you like to wrap your finger around the bar when on the hoods then you'll find it very comfortable.

It was nearly problem-free riding, thanks in part to the pro Shimano mechanics who dialed in my bike. Maybe the lesson here is to hire a pro gravel mechanic. You will probably also need to install another derailleur cable to get the derailleur working. You can find these cables here. Some readers will likely note Shimano already has clutch mountain bike derailleurs that can be paired with electronic shifting for 1x systems. With the new Ultegra RX derailleur, Shimano expands compatibility to mechanical road shifting and suggests there is a benefit in having a clutch rear derailleur with double front chain rings when riding gravel. You can use this kit with all mechanical 11-speed Shimano shifters. So whether you have Ultegra, 105 or Dura-Ace, this derailleur will work perfectly with the shifters.

Shimano also had its pro team liaisons at the Almanzo event. They were somewhat mum on the Ultegra RX’s future in professional road and cyclocross racing. Word about the Ultegra RX first came out when the Trek-Segafredo team test rode the clutch-based derailleur before the Tour of Flanders spring classic. The team did not race with the Ultegra RX in Flanders, but they did at Paris-Roubaix. As one of the reps pointed out, the impact of the new derailleur did not show in the results. Potenza is a very good groupset, but when I tested it, it was pitched against Ultegra 6800 and this new R8000 group has moved things up a notch.

Updated May 24. Shimano is known as a company that does not chase after trends, so its recent release of the clutch-based Ultegra RX rear derailleur is a sign the Japanese company thinks the popularity of gravel riding has some staying power. SRAM’s 1x clutch-based derailleurs have become popular with U.S. cyclocross racers— and a number of new gravel bikes—but Shimano representatives told Cyclocross Magazine and other journalists the new derailleur was designed primarily for gravel riding. Since the beginning of 2018 I've ridden the new Ultegra on loads of bikes in a range of setups including mechanical and electronic gear systems, and both rim and hydraulic disc brakes, so this has turned into a bit of a longterm test review as I've really been able to put it through its paces.

The latest iteration of the Shimano Ultegra groupset, R8000, offers a huge leap in performance and aesthetics over the previous 6800 version which makes it an absolute joy to use. I can't see any reason to spend more on a groupset – the only question is whether it does enough to justify its price against its cheaper sibling, 105. A number of European cyclocrossers, including Mathieu van der Poel, Sanne Cant and the Telenet Fidea team, race on Shimano components. Although SRAM’s clutch-based derailleurs have become a favorite for many U.S. cyclocrossers, the Shimano reps said none of the athletes have committed to using the new clutch-based system this fall. Shimano has made no specific claims as to how much stiffer the new R8000 brakes are over the outgoing 6800-series model, but the latest Dura-Ace brakes are reported to be 43 percent stiffer than the previous generation, so we can likely expect similar claims here. The second advantage is that the design makes it possible to mount bigger cassettes, with both the short and long cage versions. With the long cage derailleur this means that you can mount an 11-34, which will be useful on climbs. From a technical point of view it creates a bigger chainring, which allows you maintain the normal crank ratios but with a bigger cassette. The new brakes also include the same ‘booster’ bar that was introduced with the new 9100-series brakes. This thin metal plate sits between each of the brake arms, bridging the gap between the pivots and is said to “reduce deformation and improve braking efficiency.”

Shifting speed feels much the same as the previous generation, but this was hardly laggy, so no complaints here. The added weight for the clutch is about 30-40g. The RD-RX805 model has a claimed weight of 280g (compared to 249g for the RD-R8050) and the RD-RX8050 weighs 248g (compared to 210g for the RD-R8000).I think i end up with about 4-5mm of gap between upper pulley and the 30T cog - If this shift has i grinding noise, i found that the gap is too small and need another 1mm or 2 to become noisy but with no "grinding" (and i don´t meen grinding noise like bad indexing - its different på grinding, more like the upper pulley hitting the cog type of sound) Thoroughly wiggling it in a workstand, the tension of the cage pivot feels a little bit stronger than the previous generation, which should help to keep things quiet on rougher terrain. Along the way I've also ridden every Shimano groupset from the 8-speed Claris through to the top-end Dura-Ace Di2, which has helped highlight just how good this groupset is. Ultegra R8000 is best seen as an overall refresh of the venerable Ultegra 6800 groupset rather than a drastically new design — lots of small refinements make the groupset an absolute joy to use with braking and shifting that is largely indistinguishable in performance from Dura-Ace 9100. If you're fitting a new derailleur, you should definitely apply assembly grease on the screw thread of the derailleur pad. You can find our selection of assembly greases here.