By Alex Evans

Published: Thursday, 14 July 2022 at 12:00 am


Although Shimano paved the way with electronic drivetrains when the brand brought XTR M9050 Di2 to market back in 2014, as soon as SRAM introduced AXS wireless electronic shifting in 2019, Di2 for mountain biking started to show its age.

Di2 was first introduced on Shimano’s road groupsets in 2009, before being ported over to the mountain bike line-up with XTR M9050 Di2 five years later, but the off-road technology has stagnated since the arrival of the second-tier M8050 Di2 setup in 2016.

In fact, Di2 for mountain biking hasn’t really got out of the starting blocks, with the existing XTR and XT Di2 groupsets confined to a dated 11-speed groupset, despite the mechanical alternatives moving to 12-speed for XTR M9100’s 2018 launch.

On the flip side, Shimano’s electronic road groupsets have been through multiple iterations over the past 13 years, most recently with the arrival of semi-wireless shifting for Ultegra Di2 R8100 and Dura-Ace Di2 R9200, and the launch of a third-tier Shimano 105 Di2 groupset for the first time, just last month.

As Shimano’s biggest competitor in the world of mountain bike groupsets, SRAM has also extended AXS shifting to its 12-speed groups over the years, and at a variety of price points, from the flagship XX1 Eagle AXS to the GX Eagle AXS as the most affordable option.

SRAM’s focus on wireless connectivity has also opened up new opportunities, including the wireless Reverb AXS dropper post and RockShox Flight Attendant wireless suspension system.

What’s going on at Shimano then?

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XTR Di2 raised the bar when it was launched as the first electronic groupset for mountain biking in 2014.
James Huang / Immediate Media

Our very own Jack Luke wrote in his 2022 Shimano wish list that he wanted to see updates to the Japanese brand’s long-in-the-tooth Di2 MTB shifting.

In one respect, his wish has come true – the launch of XT Di2 HyperGlide+ marks Di2’s move to 12-speed but, while it’s a step in the right direction, Shimano hasn’t been able to lose the cables, and the new drivetrain is limited to use with electric mountain bikes.

The brand would argue this is in the name of integration.

Drawing electricity from the main ebike battery to offer wired power to the derailleur and shifter seems sensible because it reduces the number of separate batteries that need to be charged, and lowers the number of individual components in the system.

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XTR M9100 moved to 12-speed in 2018, but Shimano’s flagship groupset remains mechanical-only.
Ian Linton / Immediate Media

By focusing on eMTBs, Di2 integration with the new EP600 and EP801 motors also helps the system deliver Shimano’s latest Free Shift and Auto Shift technologies, where, just like the web of internally-routed cables hidden within your bike’s tubes, the new features are all fully intertwined within the combined assistance system and Di2 groupset.

Free Shifting enables pedal-free shifting and, in the case of Auto Shift, you also have the option for the groupset to take all thinking out of the equation completely with fully automatic shifting.

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While Shimano’s all-new XT M8150 Di2 electronic drivetrain is an exciting step forward for ebikes, we want to see a new Di2 groupset for non-assisted bikes, too.
Shimano

But as I sit here typing this on my wireless keyboard, on a computer connected wirelessly to the internet, wirelessly hotspotting my phone’s wireless 4G connection, why couldn’t Shimano have ditched at least some of the cables?

Power may be the biggest issue. But SRAM has managed to downsize its derailleur batteries without issue (the same goes for the batteries used to power the Reverb AXS dropper and RockShox Flight Attendant), and the whole AXS ecosystem requires no wiring at all.

I’m genuinely excited about the ebike-specific 12-speed Di2 launch, and the integrated approach Shimano has taken by combining Di2 with its latest motors, but it feels like a stop-gap to what should be Shimano’s next big MTB launch – a fully upgraded, next-gen Di2 groupset.

While improvements can be made to lever feel, for the most part, Shimano has already got the M9050 and M8050 Di2 derailleur shifting pretty much spot-on.

Shimano has also made significant progress with its wireless technology elsewhere, with improved functionality and customisation through the eTube app, and the semi-wireless shifting we’re now seeing on the road.

Across Shimano’s three latest road groupsets, the shifters are powered by coin-cell batteries and wirelessly communicate to the derailleurs, which are in turn wired to a central battery in the frame.  But given the dominance of 1x drivetrains in mountain biking, and the lack of a front derailleur, what approach would Shimano take to ditch wires, at least in part?

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Shimano’s Di2 technology for road bikes has received a lot of love, most notably with this summer’s launch of 12-speed 105 Di2.
Fairlight Cycles

Indeed, when will Shimano pull the pin on the next-gen Di2 components grenade and blow our minds with, we hope, a wireless electronic groupset that puts the brand back on the map for riders who aren’t on ebikes?

In my eyes, Shimano could one-up SRAM if it took an entirely new approach to electronic shifter feel, and if the derailleur weight could be reduced, they’d make some gains against their main competitor.

On a personal level, I’d love to see Shimano’s tension-adjustable clutch on a wireless, electronic derailleur; low clutch tension is one of the main drawbacks of SRAM’s Eagle AXS derailleurs.

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Shimano’s development of Di2 for mountain bikes has stagnated since the launch of XT M8050 Di2 in 2016. Will it now receive a shot in the arm?
Josh Patterson / Immediate Media

If the brand can offer those things, my attention will be well and truly grabbed. However, Shimano has a track record of only launching products when it’s fully ready to do so.

Perhaps we should see the launch of XT Di2 M8150 as a bit of palate cleanser between courses, washing away the taste of M9050 and M8050 with a familiar but altogether different flavour, in preparation for the next course of a fully-fledged XTR Di2 M9250 and XT Di2 M8250 launching in the near future.

Watch this space.