Shimano finally launches 12-speed 1x GRX Di2 – and it's fully wireless

Shimano has announced its first fully wireless electronic gravel groupset – GRX RX827.

Based around the new 12-speed RD-RX827 wireless rear derailleur, GRX RX827 is a 1x gravel groupset that borrows heavily from Shimano’s recently launched Deore XT Di2 M8200 groupset.

The launch sees Shimano complete its 12-speed gravel groupset range, with the Japanese brand now offering mechanical and electronic groupsets for both 2x and 1x drivetrains.

GRX RX827 leverages existing parts from its mechanical equivalent, with the wireless rear derailleur and 1x-only left-hand Di2 shifter being the only two new parts.

Nevertheless, there are plenty of details to cover and, of course, weights, specs and pricing to reveal, so let’s dig into everything we know about GRX RX827.

Read more SRAM and Shimano groupset news

• Shimano finally goes wireless with new XTR Di2 groupset
• Deore Di2 is Shimano's cheapest-ever electronic MTB drivetrain – but what's happened to mechanical?
• Shimano Q’Auto brings battery-free automatic shifting to your bike
• New SRAM Force and Rival AXS XPLR bring 13-speed gravel gearing to a lower price point

Shimano goes wireless for gravel

Though it took Shimano years to launch its first fully wireless Di2 groupset, it has launched four in this month alone.

Starting with XTR Di2 M9200, we’ve since seen Deore XT Di2 M8200, Deore XT Di2 M6200 and now GRX RX827 in quick succession.

Though we’ve only tested XTR so far (don’t forget to read our in-depth XTR Di2 M9200 review, if you haven’t already), Shimano appears to have achieved this through the time-honoured strategy of sticking with one overarching design, and using cheaper, heavier materials to bring parts down to more accessible prices.

With GRX RX827, that almost certainly means a small downgrade from the carbon pulley cage used on the XTR Di2 M9200 rear derailleur to an aluminium one, as on Deore XT Di2 M8200.

The weight of a GRX RX827 rear derailleur increases to a claimed 449g without a battery, compared to 416g for an XTR Di2 M9200 rear derailleur.

Otherwise, though, the design is practically identical.

The GRX RX827 rear derailleur uses the same wireless technology, the same BT-DN320 battery, the same ‘skid plate’ designed to shrug off knocks and bumps, and so on.

The claimed battery life is also the same, at “700 to 1,000km, depending on riding conditions” (ie, how often you shift).

In fact, as far as we can tell, the GRX RX827 rear derailleur is essentially a rebadged Deore XT Di2 M8200 rear derailleur – there are no obvious discernible differences between the two.

One thing to note is that the GRX RX827 rear derailleur is only available in a long-cage ‘SGS’ format, for use with a 12-speed 10-52t cassette.

There’s no short-cage ‘GS’ option compatible with the new 9-45t cassette introduced with Shimano’s new XT and XTR mountain bike groupsets.

That said, it appears there’s nothing stopping you from mounting a Deore XT or XTR GS rear derailleur and pairing that with GRX shifters to your gravel bike if you wanted to use that cassette instead.

Though we’ve yet to test all of the various combinations – and haven't seen full compatibility charts – it seems all of Shimano’s new wireless rear derailleurs will communicate seamlessly with its existing 12-speed wireless drop bar shifters.

The GRX DI2 RX827 rear derailleur is priced at £429.99.

1x-only drop bar shifter

Although the new GRX RX827 rear derailleur is compatible with the existing 12-speed GRX Di2 ST-RX825 shifters, Shimano is also launching a 1x-specific left-hand shifter to complement the RX827 rear derailleur.

The only difference is that the BL-RX825-L shifter loses the two Di2 shifter buttons from behind the brake lever, shaving off a claimed 19.5g.

The price, however, sees a far more significant drop – dropping down to £299.99, from £399.99, for the BL-RX825-L shifter, hose and BR-RX820 brake caliper.

Shimano GRX RX827 groupset prices

In total, a complete Shimano GRX RX827 groupset costs £1,739.90 / $2,282 / €2,011.90.

In terms of weight, Shimano's claimed figure for a complete GRX RX827 groupset is 2,987.5g. On paper, that’s a little more than 200g heavier than SRAM’s recently launched Force XPLR AXS groupset, which weighs 2,770g.

At £2,102 / $2,358 / €2,345, SRAM’s 2nd-tier 13-speed gravel groupset looks a fair bit more expensive, but it's worth noting that price includes a spindle-based power meter crank upgrade, which costs €367.

Of course, there’s usually some difference between claimed and actual weights, and RRP’s and real-world prices, so expect the Shimano figures to vary slightly as well.

A new alloy gravel wheelset

To complement the GRX RX827 groupset, Shimano has also announced a new “budget-friendly” aluminium gravel wheelset – the snappily named WH-RX180-TL-700C.

According to Shimano, the wheelset is “designed to deliver exceptional strength and reliability for any adventure.”

Featuring low-profile, hooked aluminum rims with a 25mm-wide internal width, Shimano says the RX180 wheels are designed to work best with 32 to 50mm-wide gravel tyres.

The rims are laced to Shimano’s own hubs, with the rear featuring a “redesigned pawl ratchet”, and also swappable between Shimano’s Micro Spline and HG standards.

As you might expect, given their afforadble spec, an RX180 wheelset costsjust $280 / €309.98.