components: Shimano Dura Ace 2017: First test with disc brakes and new Di2 functions

Test: In France, shortly before the start of the Tour de France, Shimano presented its new evolution of the Dura Ace road bike spearhead last year. To date, however, only the purely mechanical variant is commercially available; in Spain we had the opportunity to test the electronic Di2 group with the new disc brakes for the first time.

Shimano's new Dura Ace groupsets were presented to the public some time ago and the mechanical Dura Ace R9100 is already installed on one or the other complete bike. However, the new Di2 group, including the first Dura Ace disc brakes, has not yet been seen or driven. That's why Shimano and the German distributor Paul Lange had invited us to the Spanish cycling Mecca of Calpe over the past few days to present the new group in detail and, above all, to gain initial practical impressions.

The worst onset of winter on the Costa Blanca in decades made the test drives in pouring rain, single-digit temperatures and gusty gusts demanding, cold and uncomfortable - at the same time, however, the conditions were perfect for putting the new components through their paces, but more on that later. First we would like to give you a brief overview of the available combinations of the new Dura Ace, the nomenclature and the respective features.

Shimano Dura Ace 2017: mechanical, electronic, rim or disc?

In the past four or five years there have been more new developments and technologies in the high-performance sector of road bikes than perhaps ever before. With the new Dura Ace generation, Shimano now brings (almost) all of these technologies, features and developments to its own top group. Unsurprisingly, the now well-established electronic Di2 technology is of course retained. Some new features in the automation and new options through the E-Tube app, which is already known from the MTB sector, open up completely new possibilities for tech-savvy riders, which we will come to in detail in a moment.

However, anyone who had already hoped for a wireless variant for this product generation, similar to SRAM's eTap, will (still?) be disappointed in this regard. As much as we tried to lure the present Shimano developers and designers out of their reserve - our questions about possible future plans remained unanswered. In any case, the decision was made for the 9170 generation to use the established and tried and tested wired Di2 technology, in order to be able to continue to give this 1000% functional guarantee, especially in the Pro Peloton.

A mechanical variant of the Japanese bicycle giant's road spearhead is still in the program. Especially in the OEM area, the demand is still huge and for price-conscious buyers who don't want to do without a Dura Ace group, this remains an attractive option in 2017.

In addition to the wireless issue, Shimano's approach to the brakes was also eagerly awaited. So while it's not a huge surprise that this year will see dedicated disc brakes at Dura Ace level for the first time, it's still remarkable because, according to Shimano, this is the first disc brake system ever to be used from start to finish was developed for use on the road.

However, rim brake fans can take a deep breath – of course there will still be rim brakes at Dura Ace level. Some technical innovations in the Dura Ace Dual Pivot brakes show that people still believe in this proven braking technology and do not want to put everything on the disc card. The arms have been lengthened and their shape adjusted to provide enough space for the increasingly popular 28mm wide tires in the future. However, so that the braking power and the pressure point do not suffer, a brake booster is now used, which is supplied as standard with all brakes, is an integral part and cannot be removed. Despite the additional component, the new rim brakes are only around 5g heavier than their direct predecessors.

Shimano Dura Ace 2017: Disc brakes under the magnifying glass

So there it is - the first disc brake at Dura Ace level and the first disc brake from Shimano where every single part was developed consistently and 100% for road use. After the numerous and extremely emotional discussions in the pro peloton after the chaotic test phase at the beginning of last season, especially with regard to a possible risk of injury, our eyes and fingers first and foremost wandered in the direction of the new brake disc. So no cover - but a quick test with the thumb on the outer edges confirms our assumptions in advance, because they feel significantly less "edgy" than before.

We spoke to Shimano developer Tim Gerrit, who confirmed to us that the edges of the new Dura Ace brake discs are now "softened" during production. So an admission? By no means does Tim mean it, but it is much more a political decision. Since this season, the UCI has stipulated that the edge angle of all brake discs used in the professional sector must be less than 90°. We are still convinced that even a 90° edge does not pose any risk of injury, but we bow to the guidelines. At the moment only the Dura Ace discs are manufactured in this form, if and when the other Shimano brake discs will follow is still unclear.

But apart from the edge, there are also a few features worth mentioning: The black aluminum cooling elements, which cover the entire inside of the pane up to the center lock mount, ensure optimal heat distribution. This is so crucial because that Centerlock mount is a crucial factor in heat dissipation. For this reason, the Dura Ace discs will not be available for 6-hole mounts. The narrower recording area would have a negative effect on the thermal behavior too much. The IceTec Freeza technology, with its aluminum core, is also designed to reliably dissipate heat from the braking surface, even during longer braking manoeuvres. When it comes to disc sizes, you can choose between 140mm and 160mm.

But now we come from the disc to the brake itself. The brake caliper is a completely new development and was designed and constructed for the exact requirements on the road. In addition to braking power, particular focus was placed on modulation. The Dura Ace should be much better and more sensitive to dose than, for example, its Ultegra counterpart, which is technically based on the XT brake from mountain bikes. Efforts were also made to achieve an inconspicuous and unobtrusive look, which in our opinion was very successful. Especially in combination with the black brake disc, the overall package is much more successful on a slim racing bike than is the case with the RS785, for example.

The assembly is done using Shimano's own flat mount standard, which also makes it possible in the case of the front brake to switch between 140mm and 160mm discs without an adapter by moving the saddle up or down through the existing alternative bores. The rear brake, on the other hand, will only be compatible with 140mm discs without an adapter, which should be completely sufficient in most cases.

There are also some innovations to report at the other end of the brake line. The big challenge for the designers of the STI grips was to maintain the proven ergonomics while at the same time accommodating space hogs such as the expansion tank for the mineral oil of the disc brakes. And indeed: the final versions of the four STI variants (mechanical/mechanical, mechanical/hydraulic, electronic/mechanical and electronic/hydraulic) can hardly be distinguished from one another at first glance. The disc brake variants only build up minimally in the upper grip area - however, the grip test shows that the ergonomics have not changed as a result.

Shimano Dura Ace 2017: New rear derailleur linkage and 11-30 cassette

With the rear derailleur of the new Dura Ace, the first thing that catches the eye is of course the new design - still elegant, but a bit more technical and futuristic than before in terms of shape and general appearance. Immediately afterwards, Dura Ace connoisseurs will notice the additional joint for frame assembly, which shifts the main pivot point slightly behind the derailleur hanger. This is already known from the MTB sector and has to do with the rise of thru-axles on racing bikes.

While the wheel tends to be removed from the front with traditional quick-release dropouts, with thru-axles it falls almost vertically downwards out of the frame. With the conventional rear derailleur mounted directly on the derailleur hanger, when changing a wheel with a thru-axle quickly - for example during a race - the rear derailleur and cassette get in the way and the change costs valuable time. However, the additional joint now makes it possible to quickly and easily fold the rear derailleur backwards - so the wheel can be removed quickly and easily directly from below.

Also new is the 11-30 range cassette. This was an explicit response to the wishes of the professional teams, where some drivers in the past also used 11-32 cassettes from the Ultegra series, depending on the race and phase of the season. However, given the cage that was too short for the Dura Ace rear derailleur, this also made it necessary to use an Ultegra rear derailleur. So Shimano saw two options for counteracting this problem: either Dura Ace-level cassettes with a maximum sprocket size of 32 teeth and two different rear derailleur lengths, or a slightly modified rear derailleur and an 11-30 cassette. In unison, the teams opted for the latter option. The new cassette comes in the gradation 11-12-13-14-15-17-19-21-24-27-30 and weighs 211g. As with the other variants, the five largest sprockets are made of titanium.

Shimano Dura Ace 2017: Bluetooth, Synchro-Shift and E-Tube App

Consistent further development is also the order of the day with Shimano's Di2 technology. The new Dura Ace 'inherits' some of the features that have been introduced and extensively tested in the course of the MTB Di2 groups XTR and XT in recent years. These include, for example, the two optional synchro-shift modes:

Shimano Dura Ace Semi Synchro Shift: When changing the chainring, the rear derailleur automatically takes over the counter-shifting on the cassette to make the gear jump harmonious.
Shimano Dura Ace Synchro Shift: At a predefined point, Di2 automatically takes over changing the chainring when shifting.

The Synchro Shift mode should be particularly interesting for triathletes and time trial specialists: For example, it is possible to switch through all available gears with two additional buttons on the body without having to leave the aero position to change the chain ring. Both modes can be adapted to personal preferences with the new E-Tube app for smartphones and tablets. The software was introduced with the market launch of the XT Di2 last year and has been constantly expanded in terms of its range of functions. After connecting to the drive, the translation used (chainrings and cassette) must be specified once. From this, the app calculates the available effective gears, the corresponding chain slip and gear combinations.

In this table, for example, the moment for changing the chainring in synchro mode or counter-shifting in semi-synchro mode can be defined. A total of five predefined shift profiles can be stored in the E-Tube app for each shift. Two of them can be stored and, in addition to the completely manual mode, can be activated and changed directly on the bike. In addition, all buttons and additional buttons can be freely assigned in the E-Tube app - this includes the buttons under the hoods. With these, for example, the displays in the Garmin can be changed.

All of this is made possible by the interaction of the new battery and the new junction box. With the latter, the wishes of the customers were listened to and the optically unappealing box on the underside of the stem is history from 2017: The new junction box replaces one of the two bar ends and is integrated almost invisibly into the overall system. In addition to a charging port, there are two LEDs and a small button. The three switching modes (synchro, semi-synchro and manual) can now be switched through by pressing this twice, which the LEDs acknowledge with a corresponding flashing.

The new placement of the junction box is accompanied by cable routing optimized by Shimano. In the future there will be a Y-cable for this, which connects all controls on the cockpit including the junction box with the rear derailleur, front derailleur and, if necessary, the battery. In the future, the handlebars and stem can be disconnected from the overall system and reconnected much faster, for example if the bike has to be dismantled for travel.

If you want to make your existing Di2 circuit compatible with E-Tube, you only need the new battery and the new D-Fly unit, which also contains the necessary Bluetooth antenna. Cost for both components: Between €200 (external battery) and €250 (internal battery).

Shimano Dura Ace 2017: The power measurement crank - pragmatic, simple and functional

Shimano's announcement in the summer that there will be a power meter in the 9100 Dura Ace group for the first time caused quite a stir. Of course, this raised high expectations and also entered a highly competitive area in which the top dog SRM was fighting with a few other contenders such as Power2Max and Rotor for a relatively small group of potential customers.

From a purely visual point of view, the power meter version of the new Dura Ace crank can hardly be distinguished from the standard version. Only a small box on the Spider indicates the inner values. In addition to two LEDs, there is a button that can be used to calibrate the power meter and a charging socket. The latter has a magnetic connection that is 100% waterproof - which we were able to convince ourselves of extensively during our test drive. The rest of the technology is completely hidden inside: The battery sits in the crank axle and inside the crank arms are the strain gauges, which are then used to calculate the performance. The left crank arm is connected to the rest of the system with a simple plug connection and can be easily removed.

Finally, the power meter sends the corresponding data via ANT+, which can be read out on a corresponding end device. Shimano promises to be able to keep up with the industry leader SRM when it comes to accuracy. Prototype tests during the last season on the training bikes of some FDJ pros also underlined a major advantage of the Shimano power meter: it is extremely energy-efficient. Even with the training workload of professionals, a charge lasted between three and four months. If you are worried about the possible additional weight: The power measurement crank should only be approx. 50g heavier than the counterpart without power meter.

Shimano Dura Ace 2017: C60 Aero wheels as clincher, tubular and disc

A lot will also happen with the wheels with the new Shimano Dura Ace generation: When it comes to rim height, they are swimming against the tide and will in future be opting for 40mm and 60mm instead of the previously taken middle course with 50mm. This is particularly exciting because the trend in the last two or three years has been towards the all-round size between 40 and 50mm and many manufacturers have even said goodbye to the high aero rims altogether.

The new wheels will be available for both rim and disc brakes and will also be available for tubular tires as well as for clinchers - the latter are all compatible with tubeless as well. While the tubular and disc brake variants rely on full carbon rims, the clincher rim for rim brakes sticks to the previously used aluminum core - you don't want to sacrifice braking performance for a few grams of weight savings and prefer to take the safe route. Also interesting: The disc wheels only come with a 12mm thru-axle – if you depend on a quick-release here, look into the tube.

The rims are new developments and many hours were spent with simulations and in the wind tunnel to achieve the best possible handling with good aerodynamics at the same time. At least the data presented allow the conclusion that this goal could be achieved. Also worth mentioning is the generous rim width, which is trendy: 20,8mm for the clinchers, 28mm for the tubular.

Shimano Dura Ace 2017: First Ride with rim and disc brakes

After so much theory, let's finally get to the first driving impressions with the new Shiman Dura Ace Di2. During our press camp in Calpe, I had the opportunity to test both the version with classic rim brakes and the new disc brake. The R9150 was mounted on a Trek Emonda SLR, for the disc brakes I got to sit on a beautiful S-Works Venge with glittery rainbow paintwork by Peter Sagan.

As mentioned at the beginning, the conditions during our stay on the Spanish east coast were rather uncomfortable. However, it was a perfect playground to test the performance of the groupset, the brakes and the wheels. However, I encountered a small flaw even before I really started pedaling for the first time: The tiny button on the new Di2 junction box is very difficult to press and switching between the different switching modes is a bit of a game of patience. In view of the fact that the desired switching mode is unlikely to be changed every day, this is rather negligible in practice.

Shimano Dura Ace Di2 test: shifting modes and performance

For the sake of comparability, I started with the usual, manual switching mode. As is typical for Dura Ace, there is absolutely nothing to complain about when it comes to the raw performance: the shifting processes are fast and precise, chainring changes are quick enough even in hectic situations and mostly almost noiseless. As usual, Shimano's top group performs even exotic shifting maneuvers under load without grumbling or bitching.

The STIs made a positive impression: The developers did a really good job on the hydraulic version of the R9170 series in particular: This can hardly be distinguished from the model for mechanical brakes and we could not find any differences in terms of ergonomics. In view of the cold temperatures that forced us into thick long-fingered gloves, we were also impressed by the new buttons on the shift lever, which acknowledge pressure with a much clearer and more tactile click than their predecessors.

Of course, I also spent a few kilometers in the new automated shift modes. I first tried the Semi Synchro Shift mode, which is certainly interesting for many riders: Actually, everything stays the same here, but the manual counter-shifting on the cassette when changing the chainring is no longer necessary. This takes a bit of getting used to, since manual counter-shifting is probably already part of it for many. However, if you leave this to the electronics, it works really well and reliably; I only found the relatively long break between changing the chainring and counter-shifting on the rear derailleur to be less than optimal.

I also gave the Synchro Shift mode a chance: During the almost two-hour ride over some larger and smaller hills in the region, I didn't have to operate the left shifter once, as the Di2 shifter did this automatically. A strange feeling and certainly not for everyone - at least the buttons on the left lever remain active, so you can intervene manually at any time and change the chainring yourself.

Shimano Dura Ace Di2 review: The brakes

On the first day I sat on the rim braked Emonda and the new Dura Ace brakes together with the C60 wheels cut a good figure as usual. The changeable conditions without rain, but with wet roads and lots of puddles made it necessary to adapt my driving style, as I never really knew how wet or dry my braking surfaces were. Because despite all the further development, you can't do magic in Japan either, and the braking power on the wet carbon flanks leaves a lot to be desired. However, once the water is down, there is little to complain about. I could hardly feel any differences to the previous generation, so the new Brake Booster does a good job and successfully compensates for the somewhat unfavorable lever forces.

The next day I switched to a Specialized S-Works Venge with the new disc brakes and was really happy about the wet conditions, to say the least. Immediately after our start we found ourselves on a flooded road in Calpe and were partly in water up to the bottom bracket. So if you have concerns that the power meter or Di2 are not waterproof: we should have successfully disproved that with this unplanned extreme test.

The rest of the ride in the pouring rain was just the right terrain to really put the new brakes to the test. The hydraulic stoppers initially respond to braking with a short squeak, but the braking force and feel are the same as in dry conditions. Speaking of braking power: I had the feeling that the Dura Ace brakes grip a little weaker than the Ultegra brakes. Don't get me wrong: The power is perfectly sufficient overall, a courageous grip on the left lever also causes the rear wheel to detach from the asphalt. However, the range from the onset of braking to the final locking of the wheel is a little larger than on previous hydraulic Shimano stoppers.

Especially in the very wet conditions, the disc brakes gave me a lot of security, especially given the fact that I didn't know the bike and the track as well as I do on home terrain. The new discs didn't cause any heat problems either, even anxious grinding brakes during long descents on wet asphalt and I couldn't notice any fading at any time. A 160mm disc was installed on the front wheel of my test bike, which I would recommend to every rider over 75kg for this reason - the few grams more weight is definitely worth the significantly better resistance to fading.

Shimano Dura Ace Di2 test: C60 Aero wheels

The conditions at the press camp weren't just tough for the braking system, the Dura Ace C60 wheels were also put to the test. Again and again, strong gusts swept across the asphalt from different directions. Of course, this is not a prime discipline for 60mm high rims, because it requires a lot of calm and concentration on the front wheel in order not to be "gone with the wind". The gusts were of course also clearly noticeable with the new Dura Ace wheels, but still remained predictable. However, the few rather short rides remain more of a model with limited value in terms of the wheels - but we will certainly have the opportunity to test the new wheels extensively and in suitable conditions again in the course of the season.

Shimano Dura Ace Di2 review: conclusion

Admittedly, we were a little disappointed when the new Dura Ace was presented. No groundbreaking innovations, instead careful further development, evolution instead of revolution, so to speak. After the first real kilometers with the new groups, however, the initial disappointment is almost forgotten. The group simply still works excellently, with the optically and technically successful disc brakes, the app functionality and, last but not least, the power meter crank, there are also some useful innovations.

So no surprises, no groundbreaking new developments, but performance at the usual excellent high level with future-proof detailed improvements. In 2017, Dura Ace should still be the benchmark for many riders when it comes to racing bikes.

Shimano Dura Ace 2017: prices, weights and availability

Finally, a few words on the two burning questions: when and how much?

We cannot yet answer both questions with 100% certainty for the German market. The mechanical group with rim brakes is already available in stores at a price of around €1.700. The Di2 variant should follow in the near future, but will be more in the price range around €2.500. Friends of disc brakes will probably have to be a little patient: the Dura Ace R9170 and R9120 will probably be available from us in the course of spring and will be slightly more expensive than the versions with rim brakes.

Those who are waiting for the performance measurement crank need even more patience: It will probably take until June before this is available in this country.

Below you will find the individual component prices for the German market. As is usual with Shimano, these are (apart from the chain and cassette) not recommended retail prices, but only approximate retail prices.

Information on the individual weights is still sparse. However, what we have already learned can be found below.

Web

www.shimano.com
www.paul-lange.de