With the launch of wireless XTR Di2 (and XT and Deore) the path is clear for Shimano to launch Shimano a wireless drivetrain for gravel.
When Shimano’s 2×11 GRX groupset was launched in 2024, everyone wanted to know where the single-ring version was. After all, the 1×12 cable-shifted version had proved popular with gravel riders who rode loaded bikepacking bikes, or who took on epic mountain pass rides that saw the bike grinding in bottom gear for hours. However, as we (correctly, as it turns out) predicted, Shimano wouldn’t launch an electric groupset capable of shifting across a 10-51 mountain bike cassette until it had replaced ageing XTR first.
With the launch of wireless, electric XTR (and the surprise unveiling of XT and Deore within a fortnight of it) the path was clear for Shimano to launch Shimano GRX RX827 – a wireless shifting groupset that has a wireless rear derailleur too. This makes Shimano’s GRX 1x groupset Shimano’s first fully-wireless drop bar group.
That’s pretty big news, given that the Tour de France pro riders don’t get that kind of stuff. Even top-end Dura Ace still features hard-wired front and rear mechs powered by a battery hidden in the frame.
On to the details…
The RX827 groupset features a single, long cage rear mech, running over a 10-51T XT-level cassette.
The mech shares all of the new developments of the recent mountain bike components: it takes a removable battery, it features a close-to the-dropout, wedge-like shape for a low profile and also has Shimano’s crash recovery system where the motor will disengage after a crash (and then re-engage, ready for more).
The cassette runs on Shimano’s Microspline freehubs – and Shimano is also launching some alloy-rimmed GRX wheels to match that will take a Hyperglide or Microspline cassette body.
The existing single chainring crank comes in 40T or 42T. Which is still not low enough, we reckon – although Shimano accept that loaded riders are probably going to run a hybrid mountain bike setup, saying “RX827 offers an electronic option for drop bar mountain/adventure bikes that utilize mountain bike crank standards.”
One thing that seems conspicuously absent is a dropper shifter option on the now plain left hand brake lever. There’s no shift buttons needed, so it seems a bit of an oversight, as a bike with a mountain bike-style 1x setup may arguably be used on more extreme terrain than an aero/efficiency purposed 2×11 big ringer.
All in all, this new GRX827 groupset isn’t a surprise – much like XTR and XT Di2 – but it will be very welcome for riders who like to venture, often fully-loaded, over steeper, rougher trails, who value that wide spread of gears over big-ring cadence efficiency.
There’s no word yet if there’ll be a more affordable 600 series level electric groupset yet, in the style of XT/Deore on the mountain bike side, but we’ll keep nudging.
p.s. we’ll also update this story later as we’re off to see the new group in the flesh at a pre-Eurobike show launch event this evening.
Silly question, why go to all the bother of releasing RX825 last year?
Clearly the next, obvious thing to do is make a proper wireless 2x variant?
I can´t imagine any of us that want 2x would choose to buy any of the internally wired road or gravel groups knowing shimano are almost certainly going to supersede them with a better product?
Although a 10-51, 12 speed cassette could make a good argument for going 1x again.
At the current rate it’ll get released next weekÂ
I’ve got no problem with either system, but the seatpost battery is far better for my most commonly used bike.  It just lasts way longer. 4 months vs 1.5weeks.
I think there’s a market for both and removing the downtube wires and shifter cables vastly simplifies it and will make it quieter.
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