Shimano Ultegra Di2 R8070 disc brake groupset – first ride review

With Ultegra this good, why would you opt for Dura-Ace?

“This is genuinely the closest to Dura-Ace performance we’ve ever come with Ultegra,” says Tim Gerrits, Shimano product manager.  

Set among the Austrian Alps is a town called Au, where we’ve come to find out more about Shimano’s Ultegra R8000 groupset series and, more specifically, the all-singing, Di2 Disc R8070 version. Shimano announced details of the latest Ultegra in June.

For all intents and purposes, under the hood, the new Ultegra is packed with Dura-Ace technology. It heralds a more integrated approach towards product development for Shimano and Gerrits is effusive in his praise of the new Ultegra.

Shimano’s newest Ultegra groupset is packed full of Dura-Ace technology (Pic: Shimano)

And well he might be, because once he gets going on the details, it’s clear that the trickle-down concept Shimano helped pioneer has itself received a shot in the arm.

No longer is tech simply transferred over from groupsets higher up the food chain, with tweaks to increase affordability; Gerrits says Dura-Ace and Ultegra are now designed together – something which becomes wholly apparent over the course of two days of riding.

Ultegra laid bare

So, what’s new? Well, headlining things for many will be the Ultegra-branded disc brake calipers that feature ostensibly the same design as the Dura-Ace counterparts, along with rotors that also have a very similar design in the Freeza fin structure, albeit lacking the black coating that distinguishes the flagship model.

The theme continues with the hydraulic (and mechanical) levers, with the same internal design as Dura-Ace – so much so that when we’re given a short tutorial on how to bleed the system, it’s a Dura-Ace setup that’s used as the guinea pig. The lever ergonomics are the same, as are the remarkably small hoods too.

Shimano’s latest second-tier groupset now comes with Ultegra-branded disc brakes

The main point of difference is that the levers revert to an alloy construction, instead of more expensive and slightly lighter carbon construction of Dura-Ace.

The rest of the hardware also sees a design that largely mirrors Dura-Ace. For example, a drive side crank arm that’s identical to its Dura-Ace sibling in its two-piece construction, and a left crank arm that’s made more cost-effective thanks to a slightly meatier, forged one-piece design.

Primed for the road, ready for gravel

At the same time, to the untrained eye, the derailleurs are mirror images too, give or take a lightweight steel cage here (Ultegra’s is aluminium) and a featherweight bolt there.

What’s important is the Shadow tech has been retained, keeping the rear derailleur more inboard to protect it in the event of an accident. It’s also capable of sporting a 30t cassette in a medium cage format, and an enormous 34t sprocket in long cage mode, giving a 1:1 ratio when matched to a compact chainset.

“This makes it really flexible for gravel use,” says Gerrits, “and means you no longer have to go to a 48t chainset if you have Ultegra on your gravel bike.”

The new Ultegra is designed to offer plenty of versatility, whether you want to use it on road or off (Pic: Pro Cycle Shots)

Of course, there are slight weight penalties here, too – the cassette is aluminium to hit the lower price point, while the actual bodies of the derailleur are alloy too, instead of a Dura-Ace-spec glass fibre resin. As you might expect, the new internals are precisely the same.

Interestingly, the new rim brake calipers are heavier than the old 6800-spec versions, resulting in marginally heavier weights for an entire rim brake groupset over the older generation (see a comparison of groupset weights at the bottom of the article). That said, these too reflect the Dura-Ace design and are bulkier thanks to a new support arm in the centre of the caliper.

“This boosts power and control in the standard calipers,” says Gerrits, “while the direct-mount calipers won’t have or need this because the support is provided at the frame instead.”

Di2 upgrade

With the Di2 version, it’s the same story as before with Ultegra’s tech mirroring – so much so, that unless weight is your primary concern, on paper it’s hard to justify buying Dura-Ace Di2 in its place. “Maybe even Chris Froome will ride Ultegra next year,” Gerrits half-jokes.

The E-Tube control centre remains, complete with phone and tablet apps, and offers an array of customisation options, from the speed of the shifter response to choosing what all the buttons actually do.

Whether you want to switch around from the traditional functionality of the standard buttons, programme the new hood buttons (first seen on Dura-Ace, naturally) to actuate a derailleur or a compatible third party device, or install and customise satellite or sprint shifters, the system allows you to tailor your drivetrain to your needs.

Got all that? Excellent – read on to find out how the daddy of the new Ultegra groupsets on show, the full Di2 Disc R8070 version, rides.

Refined race-ready shifting

Setting out from the hotel in Au, our route almost immediately veers off the road and onto the quieter bike paths found all across Austria. The levers feel immediately familiar and easy to hold, not surprising given the likeness to the Dura-Ace design we’ve now had some time to get to grips with. The groupset, by the way, is fitted to a Specialized S-Works Venge Disc and we’ve got a full day of riding ahead of us.

We emerge onto the open road after and soon turn off towards a small local climb that slaps us in the face as soon as we roll to its base. Up and up it rears to an initial steep gradient of around 15 per cent, and with Ultegra set up in manual mode (rather than the Semi-Synchro of Full Synchro options that automatically actuate rear and front shifts respectively, I’m in full control of the derailleurs and well-placed to test the more powerful motors R8070 has received over the previous 6850 Di2 group.

Waiting a touch too long to shift, I press the textured button and the chain flicks down onto the small ring with an assured whir from the front derailleur. The new Ultegra buttons now have a more positive ‘click’ to them, another feature ported over from Dura-Ace and somewhat addressing one of the main criticisms of Shimano’s electronic groupsets.

Shifting has been refined on the new Ultegra groupset (Pic: Shimano)

Challenging the groupset further when the gradient eases, I shift up to the big ring once more under significant load, and the chain engages and grip onto the teeth smoothly and effortlessly, while I then place the system under further strain by holding the rear shifter down, asking it to move up the cassette to compensate at the same time.

There’s a tiny, almost imperceptible pause as the system gets to work, but the experience is smooth and as effective as can be hoped for – arguably quicker than when the Semi-Synchro mode is switched on so the groupset can perform this task on its own. However, shifting this way is slightly more hazardous when you consider Semi-Synchro moves the rear derailleur marginally after the front so that the chain is put under less stress, reducing chances of shipping said chain. Nevertheless, it’s a resounding pass from the outset for loaded shifting.

New Ultegra disc stoppers

Cresting the top of this climb of a few kilometres, the descent brings with it the chance to bed in the new hydraulic disc stoppers. It’s clear Shimano has put a lot of effort into making disc brakes more manageable than before, with an initial application that is far less harsh than I’ve experienced on its other non-series disc stoppers, including the very good RS805 system aboard the BMC Roadmachine 01 we tested at the beginning of the year.

Instead, you can grab a handful of brake – a potentially dangerous thing to do on older systems because of the tendency for pads to immediately bite hard into the rotors – and the initial power is strong, yet not shocking. Adapting to the system is a breeze if you’re still a rim-brake devotee, while Shimano seems to have managed to maintain all the modulation and ultimate power it had with its old Ultegra-level system.

A further meander along the valley later, and we encounter the big climb of the day – the Bodële pass – which after a couple of kilometres drag, is a 5km ascent at an average of eight per cent.

Here’s where the real work begins, and while I know I can count on the Venge to provide a (very) competent platform for Ultegra to do its work, there’s no doubt the entire system, from refreshed and beefed-up chainset to the new top buttons on the levers that allow easy changes at the cassette even when bearing down on the machine, is a seriously sorted-out piece of kit.

There’s no lag at any point of the climb, with changes actuated quickly and efficiently so that my ideal resting cadence can be settled on with ease, while the bike responds superbly given the light – albeit not quite Dura-Ace light – rotors that means the deep section wheels don’t feel as cumbersome as they might.

The new gruppo proved itself to be a seriously sorted-out piece of kit when the roads pointed skywards (Pic: Pro Cycle Shots)

On this climb, it also starts raining. With roads and bikes slick with water, as well as a little oil from a summer of road traffic, it’s an ideal time to test out the brakes in the wet too – often highlighted as a lead benefit of disc brake performance.

Once over the top, I don my waterproof and begin the descent. At the top it’s soaking wet, yet by the bottom it’s almost bone dry, with the sun shining once again. The varying conditions ensure it’s almost perfect for an initial test.

I could take you through a corner-by-corner recount of the experience, but the take home message is that Shimano’s Ultegra disc brakes are frankly excellent; quick to offer a controlled bite, with all the modulation and control you’d hope for in the wet or dry.

Even the changeable road conditions can’t flummox the brakeset, and although there was a fair amount of squealing to be heard from my brakes under heavy load, it’s hardly surprising given the fact that they’re brand new and these are the most testing of conditions.

By the bottom, when the system has dried out, the Freeza rotors (complete with the cooling fin design introduced from Dura-Ace) are doing a great job of managing the ever-increasing heat in the recently rediscovered warm sunshine and the noise subsides. Brake fade? Not a hint of it.

Specialized S-Works Venge Disc, Shimano Ultegra R8070, pic - Ashley Quinlan
Specialized S-Works Venge Disc, Shimano Ultegra R8070, pic - Ashley Quinlan
Specialized S-Works Venge Disc, Shimano Ultegra R8070, pic - Ashley Quinlan
Specialized S-Works Venge Disc, Shimano Ultegra R8070, pic - Ashley Quinlan

Slick Di2 operation

Day two on the new Ultegra R8070 groupset brings with it more of the same, with a long 15km ascent of the Furkajoch climb, and the experience, if anything, feels even more complete than ever.

Riding up the initial grades of around 15 per cent, I rise and fall in the saddle looking for maximum power transfer from the beefed-up crankset, while placing  my thumbs over the new hood buttons that have been programmed to actuate the rear derailleur.

It’s a revelation to me – I practically ignored the functionality when we got hands on with a Dura-Ace Di2 Lapierre Aircode in June – but on a climb it offers a fresh position to hold the bike in, and a comfortable one at that.

Moreover, I find it’s completely natural, and actually renders the satellite shifters a bit superfluous given that I get on really well with the new ergonomics of the hoods themselves. Ok, the buttons themselves actually sit under the joint of my long thumbs so aren’t perfectly placed under the pads of the digits, but it’s easy to bring my thumb back and press the button, or indeed use the joint as the pressure point itself.

For the second day I’ve got Semi-Synchro on the go as well (while also dipping my toes in Full Synchro mode), and while I prefer the former for the extra control it gives at the front derailleur, both are perfectly valid ways of operating Di2.

To recap, if you’re not familiar, Semi-Synchro automatically operates the rear derailleur are a front derailleur change in order to compensate for the change in cadence, while Full Synchro automatically operates the front derailleur according to the position of the rear mech.

Everything works perfectly – indistinguishable from the Dura-Ace Di2 drivetrain thanks to identical motors, lever ergonomics and buttons – and there can be no higher praise.

With Ultegra this good, why would you use Dura-Ace? It’s a question we’re struggling to answer after our first ride with the new groupset

Of course, you could argue that you like the sleek ergonomics of SRAM’s wireless eTap system, but given that we’ve got a couple of fresh BMC Teammachine 01s knocking about at this launch on which wires are almost completely invisible, Shimano’s views on the innovation – ostensibly arguing ‘why do it at all if the benefits to the consumer aren’t tangible in the ride experience?’ – make some sense.

Once cresting the top in the bright sunshine, a safer, faster descent back down the climb follows back down to the town of Au. And with that solid and dependable Ultegra disc brake system allowing me to push hard into corners with super confidence, and a Di2 setup that feels identical to its Dura-Ace sibling (while looking ostensibly the same too, give or take a flash of black here and there), I wonder to myself…  why would you opt for Dura-Ace Di2 at all?

Gerrits himself says he doesn’t know, and to be honest, on the power of my first experience, neither do I.

Shimano Ultegra and Dura-Ace weight comparisons

Mechanical rim

Ultegra R8000 2,512g

Ultegra 6800 2,466g (-46g)

Dura-Ace R9100 2,176g (-336g)

Di2 rim

Ultegra R8050 2,353g

Ultegra 6870 2,340.5g (-12.5g)

Dura-Ace R9150 2,047g (-306g)

Di2 disc

Ultegra R8070 2,627.6g

Ultegra 6870 + ST-785 2,824.6g (+197g)

Dura-Ace R9170 2,377g (-250.6g)

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