Shimano XT Di2 with Auto- and Freeshift: The automatic shifting system in the test

Shifting gears used to be so complicated. Three chainrings at the front, nine at the rear: 27 possible combinations, many of which made no sense at all or were very close together. Since the switch to single chainrings at the front, shifting has become much simpler. Especially on an e-bike, where the motor can sometimes help with a gear that is too high. Shimano and, incidentally, competitors such as Sram and Pinion now want to make shifting even easier.

Automatic gearstick is the keyword. The driver no longer changes gears manually, but an algorithm decides which gear is the best. Ideally, you won't have to touch the gear lever at all. But the automatic gearshift promises more than just greater convenience. Shifting should now also be possible in previously impossible situations. For example, when you are braking into a tight bend on a wild descent and would like to have the right gear ready to accelerate.

With Shimano, as with its competitors Sram and Pinion, this is made possible by communication between the electronic gearstick and the e-bike motor. Bikers can set two different automatic modes on the Di2 gearstick via the E-Tube app so that the drive takes personal preferences into account in terms of pedalling and shifting speed. This allows you to adjust the desired cadence, responsiveness and a starting gear to your personal requirements. But how well does the automatic shifting work in practice? We have already extensively tested the new electronic Di2 shifting system including all automatic functions.

The facts about the Shimano XT Di2

• Pure E-MTB gearstick that communicates with the motor
• Automatic shift function (Auto-Shift)
• Shifting gears while rolling without pedalling (Free-Shift)
• Only compatible with EP 801 and EP6
• Wired system, power supply via e-bike battery
• Adjustable via display menu and E-Tube app

The components of the Shimano XT Di2 drivetrain

Compatibility of the new Shimano XT Di2

The basic prerequisite for the new functions is communication between the gears and the motor. The new Shimano Di2 XT and Cues groupsets therefore only work with the latest generation of Shimano motors EP801 and the EP6which Shimano presented shortly before Eurobike 2022. The biggest innovation in this generation, apart from the higher peak performance of the EP801, is the new electronics with CAN port.

The Previous EP8 drive therefore works not with the new XT Di2. For our first ride impression, we had a 2023 Bulls Sonic EVO EN-SL at our disposal, but we have since been able to significantly expand our test impressions with other models from Bulls and Centurion. Always on board: the new EP801, the XT Di2 and the robust Linkglide components (chain and cassette). Incidentally, the choice of chain and cassette is crucial for the electronic Di2 drivetrain. This is because the autoshift function only works with the robust Linkglide when pedalling under load. With XT Di2 and Hyperglide, only the Freeshift function (shifting while rolling without load) is enabled. The Linkglide parts are not entirely new. However, they have not yet been installed on sporty E-MTBs. However, this will change with the new Di2, as our test bikes show.

>> Update: In addition to compatibility with Auto- and Freeshift, the Shimano EP801 also offers more power than its predecessor. Read more here in the test

Goodbye to wear and tear? The Di2 drivetrain with Linkglide components

With the chains and cassettes with Linkglide technology, Shimano offers robust components that are explicitly designed for the higher loads on e-bikes. The well-known counterpart to this is the sportier Hyperglide technology. Instead of twelve (Hyperglide), Linkglide only offers eleven gears. The 11-speed cassette relies on thicker sprockets and a gradation of 11 to 50 teeth (instead of 10 to 51 for the familiar 12-speed Hyperglide cassettes).

The more robust design should drastically increase durability. In addition, the shifting aids of the sprockets have been adapted so that the gear changes are gentler, but no longer as snappy. This should significantly reduce the forces on the chain and cassette and is presumably also the reason why Autoshift can only be combined with these parts. In principle, e-bikers and manufacturers will be able to choose between the durable 11-speed Linkglide and the familiar, faster Hyperglide with twelve gears. Incidentally, we can give the all-clear when it comes to shifting speed. Even with Hyperglide, the gear changes are still more than fast enough for demanding trail rides and difficult uphills.

How the new Shimano XT Di2 drivetrain rides

The first aha effect is completely unspectacular in manual mode: get on, start rolling, change gear - and the desired gears are instantly selected. Sounds obvious, but it's not. This is because the lever ergonomics and shifting logic of other electric gearsticks differ significantly from their mechanical counterparts. Both with the Di2 predecessor as well as with the Sram AXS you need to get used to the controls. Not so with the new Shimano XT Di2. The levers are positioned very similarly to how mountain bikers have known them for years with mechanical gears. Getting used to it? Not necessary! Only the two-way operation with the index finger is omitted on the Di2.

The pressure with the thumb on the two levers is defined and has a character somewhere between the super-direct, electronic click of a Sram AXS and the mechanical feel of the predecessor Di2. The selected gear is shown on the Steps display. Shifting is crisp, but a shade slower than with Sram's old AXS. Sram's Transmission is now taking a similar approach here, with a slightly slower shifting speed in favour of durability. And it's clear that the shifting speed is limited by the Linkglide chain and cassette, not by the Di2 components. But even with the Linkglide wear parts trimmed for durability, shifting is absolutely fast enough even for the sportiest E-MTB use and tricky uphills. But what can the revolutionary automatic functions do?

Di2 shifting with Free-Shift: shifting without pedalling

We've all been there: on the ups and downs of an undulating trail, you're hurtling towards a steep climb. There's no chance of pedalling to shift into the right gear. With Free-Shift, one push of the Di2 lever is all it takes for the motor to rotate the drivetrain even without turning the pedals. As long as the bike is rolling, you can change gear without pedalling. In practice, Free-Shift works perfectly, even if the shifting processes take a little longer than when pedalling. However: Free-Shift has its logical limits. The cassette can only rotate as fast as the wheel. This means that gear changes take considerably longer at very slow speeds. If the rear wheel locks when braking, the Shimano Di2 system will not shift. Shifting is also not possible when stationary.

Auto-Shift: Ghost-Shifting 2.0

The automatic mode is the most revolutionary new feature of the Shimano Di2 electronic shifting system. However, in order to feel comfortable with the system, it is almost essential to adjust it using the app. The first step is to select the desired cadence, to which the entire control system is orientated. Very nice: Since an update, this can also be done easily on the e-bike display and can therefore also be easily adjusted during a short stop on the tour.

And one thing is clear: tastes differ when it comes to cadence. If you start with an unsuitable value, you won't be happy with Autoshift. You'll either pedal like you're on a hamster wheel, or you'll be kneading unpleasantly thick gears. Two automatic modes can be pre-programmed in Shimano's E-Tube app. For example, in mode 1 you can commute to the start of a trail or to work with a relaxed cadence and in mode 2 you can set off on a long climb or a steep trail with a much sportier pedal stroke. The additional button on the gear lever allows you to switch between the two automatic modes while riding or take control manually.

Only unfamiliar at first: The automatic gearshift in everyday life and on easy trails

In practice, Auto-Shift just feels unfamiliar at first. The gear changes are unprepared, and the cadence does not always match your expectations exactly. But once you get used to the automatic system, it shifts gears surprisingly reliably, even off-road. A lap of the Isar trails without touching the gear lever even once? That works surprisingly well once the basic setting is right.

Auto-Shift provides real added value, especially on flat trails or downhills. Thanks to Free-Shift, the Di2 immediately shifts to the right gear when braking. This means that you never have to worry about the right gear when accelerating after bends or on fast descents. Less experienced bikers in particular, for whom shifting in demanding passages causes additional stress, can benefit from this. This is because they have more capacity to concentrate on the terrain.

Especially when the terrain is not too demanding, even real pros have fun with the automatic. If your finger sometimes twitches towards the gear lever at first, you will soon be pedalling along calmly and even miss the automatic a little when you switch to classic gears. On downhill trails with rapidly changing speeds, Free-Shift is even a real flow booster. Just brake, pedal and enjoy the trail. Shifting downhill has never bothered us before, so the comfort gain from the automatic is surprisingly large.

However, the automatic system still feels somewhat immature in some cases: The electronics do not always recognise situations quickly enough. For example: If descents, tight bends and uphills alternated in quick succession, we occasionally ended up in too high a gear despite the automatic and had to re-steer manually. Even riders with a more aggressive riding style will not leave their skills entirely to the automatic mode. Short, hard braking before corners, with slippage at the rear wheel, followed by firm acceleration - the automatic gearshift cannot keep up quickly enough. The good thing is that even in automatic mode, you can always shift gears manually to give the Di2 a helping hand.

Shimano Di2 Autoshift is not a solution for everyone

The automatic transmission also reacted inappropriately to torque changes and acceleration in some situations. For example: If you simply go into the pedal stroke on an uphill section to accelerate, you don't necessarily want to change gear. However, the automatic shifter shifts to an easier gear due to the higher rider input. You can influence this effect by setting the responsiveness in the app, but the automatic system then also reacts more slowly in riding situations where this is not desired. For example, if you enter an uphill section at full speed and the automatic system does not downshift quickly enough.

Things can get particularly tricky on demanding uphills. Here, Auto-Shift does not take the riding situation into account and shifts gears in the middle of a step or when pedalling into corners, for example. This disrupts the flow of the ride. Experienced bikers use a manual gearstick to select the right gear before entering the key section, but Auto-Shift is logically unable to anticipate this.

Tip: In the app, the automatic can be programmed so that the Di2 gearstick acts independently when rolling (Freeshift), but the rider shifts manually when pedalling. In our opinion, this allows experienced bikers to get the most out of the automatic functions. By the way: Autoshift during coasting should also work with the Hyperglide wear parts and thus 12-speed systems, as the forces are lower here than with full rider and motor thrust.

Conclusion on the Shimano XT Di2 with Auto and Free-Shift

The functionality of the new Di2 is impressive, and the ergonomics are particularly pleasing. We could hardly have imagined beforehand that an automatic gearstick could work off-road. But Auto-Shift does an amazingly good job. Flatter trails, steady climbs, demanding descents - no problem at all, you could simply unscrew the gear lever here. The system can help less experienced bikers on the trail to concentrate on the essentials, and even experienced riders will absolutely love the automatic gear preselection via Freeshift downhill. On demanding climbs with sudden counter-climbs or steps, however, the automatic system reaches its logical limits. An experienced biker shifts gears with foresight, which the automatic system cannot do. Great: The robust Linkglide chain and cassette shift crisply enough for even the sportiest E-MTB use and could significantly improve the service life of the drive. We are looking forward to long-term experience and wear tests!