Shimano GRX is very much a well-established part of the gravel scene now, and while last year saw the launch of a cabled 12-speed GRX, we are now seeing the launch of a 12-speed Di2 version. The headline changes are, beyond the addition of an additional sprocket, a revised hood design to better mesh with flared bars, and added button functionality as well as the ability to use satellite shifters.
Like Dura-Ace, Ultegra, and 105, the new GRX Di2 (RX825 in Shimano coding) is semi-wireless, with wireless controls at the hoods, but a hardwired connection between the battery and the front and rear derailleurs. While we have seen a patent recently for a fully wireless, 13-speed Shimano groupset, it is at least now clear that this wasn’t a new GRX.
