Having proven itself as an impressively reliable system, new Dura-Ace Di2 9150 will offer more refinement than innovation. Those closely watching the mountain bike world may be privy to such changes already, as the previously released XTR Di2 and more recent XT Di2 teased the many features to come.
Perhaps the biggest news is the upgraded wireless communication, with both ANT ‘Private’ (works with ANT+) and Bluetooth connectivity. This new addition is the centerpiece to a number of new features including synchronized shifting.
The ANT is to be used for head unit connectivity, displaying the likes of battery life and gear selection. Bluetooth is currently only destined for connection to Shimano’s soon-to-be-released ‘E-Tube Project’ app, but it’s a tremendous upgrade over the current wired-only (and Windows PC-only) setup. The app will be available for iOS and Android users, on either mobile or tablet. It’ll allow access to common customization interests including shift settings, shift button purpose, shift speed, and wireless firmware updates. More detailed diagnostics, such as hardware troubleshooting, may likely still call upon a shop with the current connection kit and software.
Named “Full Synchro Shift,” the new Dura-Ace Di2 can be customized to reduce your shift input by automatically controlling front shifting based on your rear gear use. As you shift up or down the cassette, the synchronized shift function will shift between the front chainrings accordingly to ensure your cadence remains consistent and to minimize cross-gearing.
This Synchro shifting has been proven in Shimano’s XTR groupset since its 2015 release, where many riders use the 2×11 setup without a front shifter fitted at all. The mountain bike groupsets do warn you of an upcoming automated front shift with an audible beep and we suspect Dura-Ace will, too.
Shimano had a Team Sky Pinarello ready for the unveiling of the new groupsets. You won’t be seeing it at the Tour though as it was prototype equipment with the new Dura-Ace disc brakes. It’s a hint at what we will see Sky on in the future though.
The left shift buttons will still activate a manual front shift as per normal. However, Shimano is so confident in its Synchro Shift technology that it’s likely to be pre-programmed on most new bikes. And of course, it can be customized or just turned off through the free app.
One customization idea we’re keen to try is to set the right shift buttons to shift the rear derailleur one direction, with the left buttons going the other and leave front shifting fully automated. For us, this would closely replicate how SRAM’s eTap shifting works, but without worry of front shifting.
We’re told a ‘Semi-Synchro’ shift mode can also be set up to adjust your rear gear position based on your manual front chainring choice. So shifting at the front will enact automatic shifts at the back to keep a consistent cadence. Such a feature is already available in Campagnolo’s EPS V3.
For those who don’t want to think at all, it’s plausible that a fully automated shift setting based on power and cadence from the power meter could potentially exist down the line. While it’s something Shimano offers in the commuting world, it hasn’t been mentioned for this performance-based groupset.
The new wireless connectivity and synchronized shifting options are the result of two new components. An updated battery plays host to the improved ‘brains’, while a specific connectivity junction box needs to be spliced into the system for the ANT/Bluetooth. This latter item will be offered in either a slim “inline” type (EW-WU111) or a slightly bulkier version (EW-WE101) that can be zip-tied in place. No doubt, we suspect the inline version to be far more popular, and perhaps even allow for it to be hidden within a frame.
Shimano has not forgotten those loyal customers using older generations of Shimano Di2 (save for the original Dura-Ace 7950, which doesn’t use the E-Tube system). You’ll be able to upgrade your existing drivetrain to Synchro Shift and other wireless features by changing to the new battery and adding a “wireless unit.” We suspect such an upgrade will be extremely popular given the sheer number of Ultegra Di2 bikes out there.
Shimano has also put some work into its “Junction A” box. This is the cable port that commonly sits underneath the stem and offers battery level indication, system reset, and a place for various wires to connect.
The new junction box can be hidden away in the frame (such as on the latest Trek bikes), and also within the end of the handlebars. Shimano’s component arm, PRO, will be releasing a range of Vibe stems and bars that will allow the junction box to be fitted and cables internally routed, keeping the front end even neater.
Three new versions of the Junction A box will be available. There will be one for use inside a handlebar, assuming internal cable routing is available. Another option is designed for placement inside a frame, such as what the new Trek Madone 9-Series (and a few others) already offers. And then there will also be the traditional version that sits beneath a stem or similar.
These new Junction A boxes and wireless connectors are notably different to what is offered in Shimano XTR and XT Di2. The mountain groups feature a small LCD screen that clamps to the handlebar, which doubles as the Junction A box and wireless connectivity. We’re told such an option will not exist on the road – and seemingly for little reason other than aesthetics and limited handlebar space. Still, the fact the Junction A doesn’t double as the wireless connectivity box feels a little undercooked to us.
Rear derailleur design gets edgy
The new Di2 rear derailleur is wholly different, while the front only receives some minor weight trimming
Just as Synchro shift is borrowed from the mountain bike world, so is the new Dura-Ace rear derailleur design. Named ‘Shadow’, the new derailleur features a low-profile design in order to better avoid potential crash damage or just generally getting bent. As a side benefit, the lower frontal profile is perhaps more aerodynamic, too.
Part of this Shadow design is an inline linkage system from where the derailleur attaches to the frame’s hanger. In recent years, Shimano introduced a Direct Mount standard to the mountain-bike world, which sees specific derailleur hangers replace this upper derailleur link for a stiffer, stronger and lighter connection while also allowing for easier wheel removal. We suspect we’ll see a similar option in road cycling soon, although adherence to tradition may prevent its widespread adoption.
Another change is the gearing capacity, with a claimed 30-tooth maximum large sprocket, as compared to 28T of the previous generation Dura-Ace. Not that Shimano recommends it, but there are many cases of older Dura-Ace Di2 being set up to work with 30 or even 32T cassette cogs. Given this, it’s likely the new derailleur may stretch to larger than claimed or recommended, albeit with potentially degraded shift performance.
Despite trends toward larger pulley wheels to decrease drivetrain friction, Shimano is keeping to its 11T sizing but with a more sleek and shapely cage surrounding them. The new derailleur design sees weight drop to a claimed 204g from the previous 217g figure.
Clutch-equipped rear derailleurs are commonplace in mountain-bike rear derailleurs, designed to reduce free movement of the pulley cage over rough surfaces to improve chain security and reduce frame slap. And despite many cyclocross racers pleading for it, new Dura-Ace rear derailleurs will not be fitted with a clutch mechanism, at least for now.
Beyond a 10-gram reduction in weight, there is little talk of changes to the front derailleur. This isn’t necessarily a bad thing given just how good the shifting already is with 9070.
Shifters get more tactile
Not a huge amount has changed with the shifters. The ergonomics have been refined and there is now a more defined hold for those low “TT-like” seated positions while on the top of the hoods.
Shifter ergonomics don’t change much with the new generation.
Most impressive is that the shift hood shape barely changes between mechanical or hydraulic brake models. Compare this to the current non-series hydraulic disc brake options, and clearly Shimano has worked hard to reduce the reach and size of its disc brake levers. Smaller handed riders will be pleased to hear that the brake-lever reach adjust now offers 41mm of adjustable range.
The new Di2 rim brake and hydraulic shifters are pretty much indistinguishable in shape and size.
After many years of light-action shifters, the buttons finally now feature a more pronounced and definitive click. It’s closer to that of a mechanical feel and is something that fixes a common complaint with previous Di2 iterations. The shift lever shape has also grown, which should help shifting when wearing full-fingered winter gloves.
Weights haven’t changed much from 9070, with the electronic rim brake shift levers (ST-9150) shaving a modest seven grams for a claimed weight of 230g per pair. With the master cylinder tucked inside, the electronic hydraulic shift levers (ST-9170) are stated to weigh 360g a pair.
Big changes for time-trial racers and triathletes
Electronic shifting has changed the triathlon and time trial markets, eliminating long-standing problems on mechanical drivetrains created by tortuous internal routing, long lengths, and sharp bends. Shimano is well aware of this and has invested plenty into improving its product for those who primarily race against the clock.
By making smart use of its new Synchro Shift technology (or, more accurately, forcing its use), Shimano has been able to greatly simplify its shifting setup. Riders choosing to use this new generation of Di2 will have to give up manual control of front shifting, but in exchange will gain lower weights, simpler operation and improved aerodynamics.
The Shimano Di2 ST-R9160 and SW-R9160 are vastly slimmer and lighter than the previous generation
For example, the extension shifters (SW-R9160) now offer a minimal 13mm external profile, compared to 52mm of the previous generation. They’re half the weight, too, at 30g per set and they simply push into place like a plastic bar plug with no dedicated mechanical clamp mechanism.
The base-bar brake levers are said to be 28% narrower than the previous generation and 28g lighter per side. Much like the road hoods, mechanical or hydraulic brake choice won’t affect ergonomics.
Availability and pricing
Shimano is claiming delivery of the new Di2 groupsets by early 2017. Pricing hasn’t been made available yet, but expect similar pricing to current 9070 offerings, with perhaps a minimal increase to account for the new wireless transmitter.