Shimano officially unveils 105 Di2 12-speed groupset

When Shimano announced its new Dura-Ace and Ultegra Di2 groupsets last summer and effectively published the obituary for its high-end mechanical groupsets, speculation on a forthcoming 105 Di2 offering quickly gathered pace.

Shimano has today put an end to any speculation, officially unveiling the new 105 R7100 Di2 groupset which brings the 12-speed shifting and semi-wireless setup from its top-tier groupsets to a lower price point. Or in other words, almost everything CyclingTips global tech editor James Huang predicted was coming in a new 105 Di2 groupset close to a year ago.

In addition to the new groupset, Shimano has also unveiled new non-series carbon C32 and C46 wheelsets, again borrowing much of the same tech from its top-tier Dura-Ace and Ultegra wheelsets and building it into a more affordable wheelset.

Looks familiar

105 Di2 you say? It does look oddly familiar, in a good way.

R7100 105 is Shimano’s new introductory-level groupset for those seeking electronic shifting and its launch coincides with 105’s 40th birthday. While the latest addition to Shimano’s electronic family borrows the Di2 brains and 12-speed shifting from Dura-Ace and Ultegra, most immediately obvious with the new groupset is just how closely it resembles its elder siblings. The new groupset features the same lever shapes and hood ergonomics as those introduced with the top-tier groupsets last year. Furthermore, the cranks and derailleurs are clearly close relations.

Seemingly these similarities extend further than just looks, though, as Shimano says the new groupset offers the same fast, precise and reliable shifting of Shimano’s Di2 groupsets to riders who have traditionally used mechanical shifting. Arguably, and to be more specific, the new groupset brings electronic shifting to just above what was previously the mid-to-high-end mechanical price point and introduces a hefty weight penalty to boot, but more on this later.

In return for some extra dosh and heavier materials, R7100 riders will enjoy Shimano’s latest Di2 system, offering 12-speed shifting in a semi-wireless setup.

Just as with Dura-Ace and Ultegra, the 105 Di2 features a wireless cockpit up front paired to the wire-connected derailleurs and battery further back. According to Shimano, this hybrid-wired-less setup “provides wireless where it matters”, with a secure wired connection in the rear of the frame where cable routing is less of an issue.

Up front, the new 105 dual control levers feature the same ergonomics and refinements made to Dura-Ace and Ultegra last year following pro rider feedback. The raised hood peak and the new lever shape are said to enhance comfort and control in every riding position, while Di2 button access was also improved for easier shifting.

Crammed inside the new hoods is all the wireless tech, with the new levers utilising Shimano’s proprietary wireless integrated circuit for secure, fast processing speed and low power consumption connectivity to the rear end of the bike.

Unlike Dura-Ace Di2 and Ultegra Di2, Shimano says there’s no option to run the new 105 Di2 fully wired to eke out a longer run time. However, the time trial setup is fully wired, using legacy controls and a similar connector adapter just like the more expensive groupsets.

Moving to the rear, and just as with the current Di2 offerings, the front and rear derailleurs are connected directly to the same internal battery used in the flagship road groupsets. Furthermore, just as with the top-tier offerings, Shimano has also integrated the battery charger and D-Fly wireless network into the 105 rear derailleur, offering ANT+ and Bluetooth connection with, as Shimano says, “most third-party cycling computers, including Garmin and Wahoo”.

R7100 is also customisable through the Shimano E-Tube project app, offering riders the option to set up the drivetrain to their personal preference with adjustable shifting speed, shifts per button, and the synchronized / semi-synchronised shifting functionality.

All this electronic computing combines to offer riders shifting across a new 12-speed cassette that Shimano says offers “the high and low gearing riders want, along with an intelligent progression of gear steps in-between”. Specifically, that means 11-34 and 11-36 cassette options along with 50:34 and 52:36 chainring combinations. There are plenty of crank length options also, with Shimano offering the new 105 cranks in 160, 165, 170, 172.5, and 175 mm lengths.

The brake callipers are also revamped and said to provide quieter, more powerful and controlled braking than the current R7000 105 braking with a fast initial contact point and 10% wider pad-to-rotor clearance. Shimano further refined the 105 braking with the lighter and smoother lever action, enhanced modulation thanks to the expanded braking control area, and free stroke adjustment all trickling down from the Dura-Ace and Ultegra levers to the new R7100 stoppers.

In good news for home mechanics, Shimano says the new 105 callipers offer a more user-friendly bleed process that can be performed without removing the calliper from the frame.

The same but different

So far so good. While we haven’t had a chance to test ride the new groupset yet, it looks every bit the Di2-level groupset with plenty of features. What then makes this a 105 and what differentiates it from Shimano’s flagship Dura-Ace groupset and second-tier Ultegra Di2?

First off, and presumably of no surprise to anyone, the 105 Di2 groupset is heavier than its siblings. According to Shimano, a complete groupset tips the scales at a touch over 3 kg, including wires and battery. That’s an additional ~560 g over a Dura-Ace groupset and ~360 g over the Ultegra-level Di2 offering.

Both those groupsets are considerably more expensive, though. As such, it’s perhaps more relevant to compare the new groupset to the 11-speed mechanical Ultegra R8000 groupset which weighs almost 350 g less. Meanwhile, the new 105’s direct competitor in the zip-zap gears segment, the SRAM Rival Etap AXS groupset, is approximately 120 g heavier than the new R7100 Di2.

Sticking with the expected differences, the new 105 Di2 is cheaper than its counterparts, but maybe not by as much as we would have hoped. At US$1,886.87 (international pricing to follow) the 105 Di2 groupset is around US$500 cheaper than its Ultegra R8100 Di2 brethren. While $500 is certainly a significant saving, again it’s perhaps more relevant to compare the R7100 to the current 11-speed mechanic Ultegra it looks set to effectively replace. Seen through this lens the new R7100 certainly shows off its less promising side, coming in at approximately US$300 more expensive.

While 300 bucks doesn’t seem extortionate for an upgrade from mechanical to electronic while gaining an extra sprocket in the process, considering Shimano has already suggested it will phase out Ultegra mechanical and with 105 Di2 effectively taking its place, this will most likely result in another sizeable bump in the ongoing upward trajectory of bike pricing in general. The cost of the new groupset alone is now approaching the price of entire carbon road bikes with Ultegra mechanical groupsets from just a half-decade ago.

No space at the inn for satellite ports or secret buttons.

Of course, we all expected 105 Di2 would be heavier and less expensive than Ultegra Di2, but, as you might also expect, there are also some less obvious differences between 105 and its older siblings. Starting with the levers, the R7100 shifters now feature two coin cell batteries in each lever, compared to the one in each lever in the existing Di2 groupsets. While the extra battery extends battery life, Shimano explains the extra real estate eaten up by the second battery means there is no space in the new levers for satellite shifter ports or the hood top “secret” button.

The new 105 levers also miss out on Shimano’s Servo Wave pivot mechanism which alters the leverage ratio throughout the stroke of the brake lever, so modulation won’t match that of the newest levers from both the top two groupsets.

Chainrings don’t go quite as big, while the front derailleur isn’t quite as small.

Notably, the 105 chain and cassette miss out on Shimano’s latest Hyperglide+ shifting technology, which presumably suggests the 105 shifting won’t be quite as snappy as the incredibly fast shifting offered by the new R9200 and 8100 groupsets. That said, Shimano was at pains to point out that the electronic shifting at the 105 level will make a drastic improvement in the quality and ease of shifting over the existing mechanical 105.

Speaking of shifting, there is a notable difference in the front derailleur design also, with the 105 offering reverting to a larger front derailleur compared to the aero offering introduced last year. Flatter-land riders and racers might also find themselves wishing for at least one more cassette ratio and/or chainring combination option.

Shimano made no mention of any rim brake option and when asked the official reply was, as always, that Shimano does not comment on future product development.

All that said, there are still reasons to be cheerful if anything I just mentioned has left you disappointed. The new 105 Di2 is compatible with R9200 and R8100 Di2 components with only a few limitations. Namely, the new 105 11:36 cassette is beyond the 34-tooth maximum sprocket compatibility of the Dura-Ace and Ultegra rear derailleurs, while the 105 and Ultegra front derailleurs are both limited to a 52-tooth maximum chainring size.

If further expenditure on mixing and matching components isn’t your thing, Shimano has confirmed it will continue to offer the current mechanical 11-speed 105 R7000.

Availability

All told, it seems R7100 105 Di2 offers lower-priced electronic shifting, 12 sprockets out back, a semi-wireless setup, and plenty of good looks with only a few features missing from the flagship groupsets. Apart from the death of high-end mechanical and a higher price point for riders previously in the same market segment, it seems 105 is otherwise good news all around.

The bad news is we can’t currently buy the new R7100 groupset. Shimano was only able to say it is expecting availability come late summer 2022 in North America. Australian availability is thought to be within the same time frame, while we are awaiting confirmation on European availability.

It was a similar timeline when Dura-Ace and Ultegra were announced last summer, and although both groupsets did come online roughly on schedule, supply was very limited. Hopefully, Shimano will have greater stock levels ready to roll out on the release date.

New RS710 wheelsets

In addition to all the Di2 groupset trickle-down goodness, Shimano has also announced two new carbon wheelsets, the C32 climbing wheel and the C46 allrounder.

Described as Shimano’s “most affordable carbon wheelsets ever” the new wheels, much like the new groupset, bear a striking resemblance to their Dura-Ace and Ultegra premium-level counterparts. Shimano says all its wheelsets now share the same DNA focusing on balancing aerodynamic gains, reducing weight, and retaining rigidity.

The new wheels are not specifically 105-level wheelsets but are a so-called “non-series” offering. However, both wheelset options are both 11- and 12-speed compatible, tubeless-ready, and feature almost identical aesthetics to the C36, C50, and C60 wheelsets launched last year.

Both wheelset options are priced at US$1,049.99 with international pricing to follow.

C32 (aka the WH-RS710-C32-TL)

The C32, as the name suggests, features a 32 mm rim depth with a 21 mm internal rim width and a 28 mm external width for mating with wider tyres. Those rim width dimensions are identical to those found on the Dura-Ace and Ultegra-level wheels.

With claimed weights of 665 g for the front and 839 g for the rear wheel, Shimano describes the C32 wheelset as a lightweight offering for riding where acceleration is key.

C46 (aka the WH-RS710-C46-TL)

The deeper C46 on the other hand with its 14 mm deeper rim height presumably offers improved aerodynamics. That 46 mm rim features the same 21 mm and 28 mm external rim dimensions and bumps the weight up to 665 g for the front and 839 g for the rear wheel.

Both wheels feature Shimano’s tried and tested (and home-mechanic friendly) cup and cone hubs and bearings and 24 spokes front and rear with external nipples.

More information can be found at www.shimano.com.

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