Shimano Ultegra R8000 Medium Box Rear Derailleur

Product Information

The company unveiled the new RX derailleur with its 2019 line of products last month and we were the first to bring you official details on the derailleur as well as the new 105 groupset. We take a look at the new clutch-based derailleur, consider its future in cyclocross and offer our impressions after riding with it over 100 miles of Minnesota gravel. The New Clutch-Based Shimano RX Rear Derailleur

The materials which this derailleur is made from are lightweight and durable. Light metals are used which makes the derailleur very strong. These metals are optimally constructed and finished so that you don't take a gram to many up the mountain with you. I love using R8000, it's pretty much my favourite groupset – and I've ridden virtually every setup going this year, at least from Shimano and SRAM. It's no lighter than the outgoing edition, but overall it works just a little bit better – more an exercise in refinement than a major overhaul, but very welcome nonetheless. Verdict

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The hood shape is very similar to 6800, but the rubber cover has had a pattern added for extra grip, like Dura-Ace, not that I really noticed a difference. 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.

Shadow Geometry shifts the majority of the derailleur mechanism below the cassette and chainstay, keeping it out of harm’s way, leaving only the main pivot proud of the frame. 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.

Ultegra FC-R8000 Hollowtech II crankset

The new Ultegra-level chain, which also works with the mountain bike groupset Deore XT, uses Shimano's SIL-TEC ultra-low friction surface treatment, a plating process that Shimano claims offers smoother running and longer wear in all conditions. We changed the chain, indexed the gears, tried to play with the b-screw on the rear derailleur, that did not solve the problem. Today I received a new bike for my girlfriend, equipped with exactly the same groupset, I see the same problem, the noise is even louder, as well as the vibrations (ask me if you want a video for this bike too).

Chain reaction Cycles and CRC are trading names of Wiggle Ltd (In Administration) registered in the United Kingdom at 1000 Lakeside, Suite 310, Third Floor N E Wing, Portsmouth, Hampshire, PO6 3EN, Particularly when I am on the big ring, and the 5 smallest gears, the transmission produces a noise which seems to come from the rear derailleur (and more precisely at the level of the top pulley, where we see the chain that seems to "vibrate" - see video). On my other bike, I have an "old" Ultegra 6800 groupset which is perfectly silent. I have never had a noise problem with it in 3 years and the bike is set up the same way as the other two.The Ultegra R8000 rear derailleur has Shimano's Shadow-Link design. With this design, which you also see on the Dura-Ace R9100, the derailleur is further recessed below the cassette, which has two key advantages: Working with your 11-speed groupset and composed using a lightweight aluminium pulley cage that goes a good way to reducing weight without sacrificing your shifting power or performance, this rear derailleur boasts an incredibly broad gear ratio. Ranging from 11-28T and going as far as 11-34T you can rest assured that you have the ability to take on the impending climb and pursue it to its conclusion. 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.

series braking was considered benchmark and I think Ultegra R8000 exceeds it in terms of power and modulation. Shifting is also on par, and while R8000 weighs a touch more, you can easily lose that weight elsewhere on the bike. Shimano Shadpw RD -The mechanism rear derailleur, SHIMANO SHADOW RD, is intended for more aggressive riding. Its super low profile design carries many benefits. Because of its low profile and single tension construction, the derailleur does not hit the chain stay in rough riding conditions. The result is smooth and silent performance. 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. Before you can install the new derailleur, you'll need to remove your chain. You can read about how to do that in this blog. You'll need a chain breaker, which you can find here. Some multi-tools contain a chain breaker. Make sure that you select a chain breaker for the right speed chain though - the size of the pins is different according to the speed of the chain.Both models come with a GS long cage that fits cassettes between 11-28t and 11-34t. Lawrence explained the company added room for the 34t cog after test rides on the steep gravel roads in Colorado. That’s pretty low for road 2x gearing, but a few steps away from the 11-42t many 1x users are used to (in case you’re thinking about a RX805 single chain ring setup). Since I started testing the new groupset, many have also asked me whether it is as good as Dura-Ace 9000 and I’d have to say, yes, pretty much.