Shimano GRX goes wireless: First look at the new 12-speed GRX Di2 Groupset
GCN's Si Richardson gets his hands on Shimano's first 12-speed electronic gravel groupset, GRX RX825
Tom Hallam-Gravells
Online Production Editor
Ever since Shimano released a mechanical 12-speed version of its GRX gravel groupset, we’ve been patiently waiting and anticipating the release of an electronic Di2 version.
We didn’t have to wait too long as less than six months later, Shimano has unveiled GRX RX825, introducing semi-wireless shifting to the GRX range for the first time.
GCN’s Si Richardson was very excited when he heard about the new groupset and even more delighted when he was given the opportunity to give it an early spin. So, having added it to his trusty Canyon Grail, Si headed to the Shimano Experience Centre in the Netherlands to test the new groupset out.
Check out his full breakdown and early impressions of the groupset in the video above, or check out a quick-fire lowdown on the major features of the new groupset.
Read more: Guide to gravel groupset hierarchies: Shimano, SRAM and Campagnolo groupsets explained
Shimano's first 12-speed Di2 gravel groupset
Both 12-speed and Di2 versions of the GRX groupset existed before, but GRX RX825 is the first that blends them together for the first time.
The first 12-speed version of GRX was released last year while an 11-speed Di2 version has been available since GRX first broke cover in 2019.
GRX RX825 is only 2x
© Shimano
The new 12-speed Di2 GRX is 12-speed only
In a move that will surprise some, GRX RX825 is only available in a 2x set-up and not 1x.
The original mechanical 12-speed GRX is available in three different set-ups. The ‘Unbeatable’ and ‘Unstoppable’ set-ups are 1x, but Shimano also offers a 2x version they call the ‘Undroppable’.
Sharing the same gearing options as Undroppable, GRX RX825 is available with a 48/31t chainset and 11-34t or 11-36t cassette, although it is also possible to substitute in a 46/30t chainset from Shimano’s more budget-friendly 600 series GRX groupset.
Shimano GRX receives semi-wireless Di2 shifting
© Shimano
Semi-wireless shifting has arrived at the GRX groupset for the first time
Until now, Di2 GRX groupsets have used Shimano’s older wired system, whereby the levers and derailleurs are connected to a centrally housed battery by wires.
That was its only system when GRX first emerged and was used across its road range too, but the road groupsets have since moved across to a semi-wireless system too, and GRX RX825 is the first of Shimano’s gravel groupsets to do the same.
In a semi-wireless Di2 groupset, the levers aren’t connected to the battery by cables, although the rear derailleur is.
Optimised shifters for flared handlebars
The new groupset required new levers, and Shimano has chosen to optimise the designs for flared handlebars.
That makes sense as most gravel bikes now use bars with flared designs, as they offer better comfort and control when riding off road.
The brake levers also have non-slip textures for added security.
Learn more about Shimano’s latest GRX Di2 groupset here. To keep up to date with the latest cycling tech, head to the Tech News section on the GCN website.
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