By Dave Rome
(CYCLINGTIPS) — Shimano's mountain bike groupsets have long offered teasers of emerging concepts that eventually find their way over to the dropbar world. And so while the company's latest announcement of fresh product is aimed at the e-bike market, the features teased could prove to be far more widely applicable.
Following hot on the heels of 105 Di2, Shimano has now announced two fresh versions of XT Di2 for mountain bikes. However, unlike the original 11-speed version of XT Di2, these new versions are designed specifically for use in the booming e-MTB segment. And joining those new XT components are some new Di2 groupsets aimed at commuter bikes, and a couple of new drive units, too.
All of these new components are pretty interesting if you're in the market for a new e-MTB or commuter, but the introduction of automatic shift functionality to a derailleur-based drivetrain is all the more intriguing.
Two new versions of XT Di2
Shimano will be offering two versions of the new e-MTB-specific Di2 shifting systems, one being a more affordable 1×11 speed version with claims of increased durability, and the other being a 1×12-speed version that effectively adds electronic control to the pre-existing 1×12 XT M8100 mechanical group.
Both new drivetrains are designed to plug directly into the equally new EP600 and EP801 e-MTB drive units, with power provided by the e-bike's main battery. And both share the same XT-level Di2 shifter, something that is also wired to the bike's central battery.
Using the M8150 rear derailleur and an 11-50T range cassette, the 1×11 version employs Shimano's recently launched "LinkGlide" (LG) technology. Sitting in addition to Shimano's other drivetrain offerings, LinkGlide is intended to provide a more durable drivetrain via a cassette that features wider sprockets with taller teeth.
LinkGlide cassettes are designed to work with regular chains and fit HG freehub bodies, but the thickened gearing spacing calls for a specific shifter and rear derailleur.
Shimano has announced a new CS-LG700 cassette that is claimed to be 200 grams lighter than the previous 780-gram boat anchor of an 11-speed LinkGlide cassette.
The subtly higher-end XT M8170 Di2 rear derailleur is designed for use with Shimano's pre-existing Hyperglide+ 1×12-speed components and makes use of the same 10-51T cassette and chain as the currently mechanical XT groupset.
Pricing, availability, and weight details haven't been provided. Expect these new drivetrains to feature heavily on complete bikes, with limited aftermarket availability due to them requiring the new EP600 or EP801 drive units for functionality.
Cues Di2
Cues is a fresh brand line for Shimano aimed at the lifestyle and commuter market. Shimano has kicked off the Cues name with two derailleur-based Di2 drivetrains, both of which are designed to plug into the new EP600 and EP801 drive units.
Not unlike the new XT Di2, Cues will be offered in both 1×10 and 1×11 variants to hit different price points. Both versions are based around the new LinkGlide cassette with improved durability in mind. The 1×10-speed version offers a maximum low sprocket capacity of 43T, while the higher-end 1×11 version can handle up to a 50T sprocket.
Like the new XT Di2, you can expect these components to be seen on 2023 complete bikes that are equipped with Shimano's latest drive units.
Free Shift and Auto Shift explained
Perhaps the biggest news shared between the new XT Di2, Cues Dis, and drive units, is the mention of a new Auto Shift functionality — the first time Shimano has offered such a thing with a derailleur-based drivetrain. Shimano has dabbled with auto-shifting functionality in the past. Its hub-gear-based Coasting System from the mid-2000s was only short-lived, while just last year we saw a new automatic shifting and e-bike-specific hub gear return to market.
Currently only available on bikes with the above-mentioned drivetrains and motors, "Free Shift" is a new setting that allows the gears to shift without you pedalling. While you're coasting, pressing the shift button prompts the motor to advance the chainring and allows for a smooth shift under controlled power. Free Shift is likely to offer real benefit when riding tight and technical trails and will surely go a long way to reducing panicked gear-crunching that is only made more severe by the power of a motor.
Joining Free Shift is a new (and optional) automatic shifting functionality aptly named "Auto Shift with Manual Override." As the name suggests, this is an automatic mode that will make shifts based on your speed and cadence, or it can be overridden by hitting the shift button. And with the aid of Free Shift, this automatic mode can even make predictive shifts when you're coasting.
What could this mean for the future of Di2?
There's little arguing that features such as Free Shift and Auto-Shift will prove a huge hit in the e-bike space, and for very different purposes. Free Shift is likely to find popularity among the e-MTB crowd, while Auto Shift will probably become a strong upsell tool for casual riders seeking a commuter.
That said, the Free Shift function isn't going to find its way onto manually powered bikes anytime soon as it relies on having a motor attached to a chainring to power the shift. And besides, there are already a few companies offering a crank-based freewheel and fixed rear hub combo to allow for pedal-less shifting when gravity mountain biking.
Instead, it's the new Auto Shift functionality that's the one to watch and in this sense, we could be looking at the next generation of Di2 SynchroShift for Shimano's road groupsets. While this may be over-simplifying things, adding a GPS device, cadence sensor, and/or power meter into the mix could provide the system with all the information required to enact automatic shifts. And while the use of speed and cadence is likely to provide too simple a function for a performance-orientated rider, the addition of power could provide exactly what a lot of riders want.
Automatic shifting certainly won't be for all, and I'd hazard a guess in saying most reading this article will be against it. But there's little denying that there's a huge market of riders out there who would rather not have to think about their gear selection and would rather just pedal. And it's a feature like this that would help strengthen the case for mechanical drivetrains going the way of the dodo (not that I love this trend).
I guess the biggest question is not if we'll see automatic shifting reach our electronic-enabled drivetrains, but rather when and who will debut it first. SRAM is already deeply invested in its own digital ecosystem of drivetrains, suspension, power meters, data acquisition devices, head units, and more. And SRAM has already managed to trickle its power meter technology down to price points where such automation will be most appreciated.
Either way, it's now clear that Shimano is quite far along with the idea, too.
