Shimano’s new RX components may be the prescription for gravel

SPRING VALLEY, Minnesota (VN) — While Shimano may have outfitted John Degenkolb’s Tour of Flanders bike in April with its new clutch-equipped Ultegra rear derailleur (Ultegra RD-RX800/RX805 for the mechanical and Di2, respectively), it chose Minnesota’s Almanzo 100, the self-proclaimed “Granddaddy of Gravel Races,” to introduce the derailleur to a select group of journalists.

At Almanzo, I rode an Allied Alfa All-Road bike built with a Dura-Ace Di2 groupset and the new Ultegra RX derailleur. While the packed dirt and occasional wash-boarded, loose gravel roads in Minnesota didn’t have a lot of chatter to them, the derailleur worked flawlessly. I experienced no dropped chains, no slapping against the stay, and a quiet drivetrain throughout the race. Because I rode a Di2 derailleur, however, I didn’t get a sense of any added lever pressure it might take to overcome the clutch tension. According to Hiroshi Matsumoto, Shimano’s lead manager for road and gravel, the tension is less than what you would experience on the brand’s mountain bike derailleurs.

After conducting several years of research to understand the variety of terrain that encompasses “gravel” riding and racing — both in terms of road surface and texture, technicality and elevation change — Shimano engineers concluded the clutch mechanism was the best solution for chain management, while also offering a quiet and efficient drivetrain.

The derailleur’s Shadow Plus clutch, similar to Shimano’s mountain bike offerings, reduces unwanted chain movement and is available in mechanical and Di2 versions. It’s compatible with all Shimano 11-speed road groups, up to an 11-34T cassette, while the maximum difference between front chainrings can be 16 teeth. The new design adds about 70 grams over the standard GS rear derailleur. The mechanical model is available for $110 and the Di2 version for $285.

“Within the U.S. and Canada, the influence [to the design] has come from the road side,” said David Lawrence, Shimano’s road and pavement product manager for North America. “There’s also some mountain bike influence, but we didn’t want to just take a mountain bike derailleur and slap it on to a road group. We wanted to hit the mark for gravel riding as well as for more versatile road riding.”

To that end, an efficient drivetrain is much more important to the road consumer, according to Tim Gerrits, road product manager and Di2 specialist for Shimano Europe. Roadies typically desire a larger range of gears, which are more tightly spaced for optimum cadence choices. Shimano’s traditional 2X format improves chain management while maintaining an efficient drivetrain, as opposed to a 1X system which loses efficiency and quietness at the extremes that it utilizes by nature.

“We’re not discounting 1X. For certain applications, that’s the right choice,” Lawrence said. “For our first movement [into gravel], the majority of people were looking for total range, so that’s where we went first.”

Which brings us to the fact that the new rear derailleur is just the beginning. Shimano will be taking further strides into the gravel world with future drivetrain pieces, as well as clothing and other components (see below).

“We recognize that we have so many specifications on the road-bike side, whether that is cyclocross, time trial, road, endurance, and so on, and it’s very hard to add more specification,” Gerrits said. “Our goal is that everything that we bring to this [gravel market] in the future, which doesn’t live under road or mountain, will live under this umbrella of RX.”

Components and softgoods

Shimano’s in-house component brand, Pro, also had several prototype gravel-specific components at Almanzo, which will be released later this year. They included two aluminum bars, one with 12 degrees of flare and ergo tops and another with and 30 degrees of flare and round tops. There will also be a dropper post with 70 millimeters of travel, external cable, and universal remote lever. Finally, Pro will release a selection of bags for bikepacking, including a top tube bag, frame bag, handlebar bag, and seatpost bag. Stay tuned for more details.

First introduced at Eurobike and Interbike in 2017, the company’s XC-5 shoes for gravel are now available in a limited-edition “camo” color scheme. Only about 1,000 pairs will be sold, and are only available at selected local bike shops (no online sales). The $150 shoe is made from synthetic leather, which doesn’t breath like mesh but keeps dirt and grit out of the shoe. It also features a “mini-power strap” that creates two zones in the shoe’s laces, allowing you to tension each zone differently depending on the size and shape of your foot. Other features include the lightweight and rigid carbon-fiber reinforced midsole, the Michelin tread that extends across the arch, and a reinforced spike mount that accepts up to 18-millimeter spikes.

Finally, Shimano has created a group of ambassadors to help them both with product design and to tell the story of gravel riding and racing to a larger audience. The 15 members include gravel icons like Dan Hughes, the four-time winner of Dirty Kanza 200, as well as shop owners, race promoters, and others who spread the gospel of gravel in their own way.

“First and foremost, their mission is to help us understand the regionality because they’re coming from all parts of the U.S. and Canada,” Lawrence said. “Every place has a different need, in a way, and they might come to us and say, ‘Ah, if only I could run a bit wider rim.’ And of course, the ambassadors are going to more naturally explain the story of gravel riding and how it’s evolved.”