Shimano, a giant in bike components, has just introduced its first fully wireless option for gravel cycling, building on recent wireless launches for mountain bikes. Unlike those full overhauls, this new offering centers on two key components designed to let riders build a clean, wireless 1x gravel setup. This means less clutter on your handlebars and potentially tougher shifting for rough rides.
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Here’s the lowdown: Shimano has released a new wireless rear derailleur and a simplified left-hand brake lever. When combined with existing GRX 1x cranksets, cassettes, and the wireless right-hand shifter, they create a complete 1x wireless drivetrain specifically for gravel adventurers. It’s less about replacing the entire GRX lineup and more about adding a highly sought-after wireless option for fans of single-chainring simplicity.
What’s New? It’s About Options
Shimano’s GRX gravel lineup already offers several choices, including a top-tier wired 2×12 Di2 electronic groupset and cable-actuated 1x and 2×12 options. The new wireless parts slot into this ecosystem, giving riders another way to configure their bike.
The core additions are:
- A new wireless rear derailleur (RD-RX827)
- A new, simplified left-hand brake lever (BL-RX825-L)
These new components are designed to work seamlessly with parts you might already be familiar with, specifically the chainrings and cassettes from the current cable-actuated 1x GRX groupset and the wireless right-hand shifter from the existing 2x GRX Di2 system.
The Heart of the Upgrade: A Smarter Rear Derailleur
The centerpiece of this wireless 1x option is the new RD-RX827 rear derailleur. It takes inspiration from Shimano’s latest wireless mountain bike derailleurs (like XTR and XT) and brings some of their robust features over to gravel.
Shimano GRX Di2 Wireless rear derailleur mounted on a bike
Crucially, this derailleur is designed for a 1x setup and primarily works with wide-range cassettes, specifically Shimano’s 10-51 tooth option. While it might work with other 12-speed cassettes, the focus is clearly on tackling steep gravel climbs with a single chainring. It’s only available in a long cage version to handle these big cassettes. For those who want even lower gears, it’s possible to use compatible mountain bike cranksets too.
Borrowing tech from its mountain bike cousins, the GRX wireless derailleur features a design intended to survive encounters with trail obstacles. Rounded edges help it glance off rocks rather than snagging. Plus, an ‘impact recovery’ function automatically returns the derailleur to its previous position after a bump, meaning you can often just keep pedaling without interruption.
It also includes a new dual-spring design for improved chain retention. This feature, also ported from MTB, helps keep your chain securely in place, even over the roughest washboard roads or rocky descents – a welcome addition for any gravel rider pushing the limits.
The new derailleur weighs in at 449 grams and offers a claimed battery life of 700 to 1,000 kilometers between charges.
Closeup of the Shimano GRX Di2 Wireless rear derailleur battery cover
Like the wireless MTB derailleurs, this GRX version features a removable battery. This is handy as you can pop it off for charging without needing to bring the whole bike near an outlet.
Removable battery being taken out of the Shimano GRX Di2 Wireless rear derailleur
Simplify Your Cockpit: The ‘Dummy’ Left Lever
If you’re going with a 1x setup (one chainring up front), you only need a shifter on the right side to change gears at the rear. Using a standard 2x Di2 left shifter would leave you with buttons you don’t need.
To address this, Shimano has released the new BL-RX825-L left-hand GRX lever. It matches the look and feel (ergonomics) of the standard GRX Di2 shifters but is purely a hydraulic brake lever – no shift buttons here.
While it only shaves off about 19.5 grams compared to a full shifter (weighing 188g), its main benefit is simplicity. It cleans up your handlebars and prevents you from accidentally pressing a non-functional button when things get bumpy. The wireless right-hand lever (RX825) handles all your gear changes and any bonus functions you might set up, like controlling a cycling computer screen.
Users can also opt for Shimano’s dropper post-specific GRX lever if they run a mechanical dropper post, or even stick with existing 2x Di2 levers and potentially program the extra buttons for other functions, although this adds complexity.
Pricing and exact availability details for these new components were not available at the time of this announcement.
In essence, Shimano’s new wireless GRX components offer gravel riders a clean, simple 1x drivetrain option that benefits from robust mountain bike technology for improved performance and reliability on varied terrain.
