Are 13-speed Di2 groupsets on their way?
A patent application filed by Shimano suggests it is working on fully wireless 13-speed electronic groupsets for both road and mountain bikes.
Spotted by the Instagram account @bettershifting, the patent images show a Shimano Di2 derailleur acting on a cassette with 13 sprockets.
The patent also details how the front and rear derailleurs could house internal rechargeable batteries. This would negate the need for a wired connection to the external battery used by Shimano’s 11- and 12-speed electronic groupsets.
Should such a design ever come to market, it seems Shimano is looking to emulate SRAM and Campagnolo, which have moved to fully wireless groupsets in recent years.
A fully wireless 13-speed electronic groupset would be the first of its kind, though.
While both Campagnolo and Rotor have released 13-speed mechanical groupsets – in the form of Ekar and 1×13, respectively – none of the major groupset manufacturers has released a 13-speed electronic groupset yet.
An unreleased clutch-equipped, gravel and mountain bike rear derailleur design is also referenced.
A 13-speed, 2x Shimano groupset
On page 7 of the patent application, Fig.10 shows a rear derailleur (which, in this case, looks very similar to the current-generation Dura-Ace Di2 R9250 model) operating in conjunction with a cassette with 13 sprockets.
Currently, Shimano’s road, gravel and mountain bike groupsets top out at 12 speeds at the rear.
The patent doesn’t provide any indication of sprocket sizes.
While both SRAM and Campagnolo have moved to offering 10t sprockets on their high-end road cassettes, Shimano stuck steadfastly with 11t smallest sprockets on its latest-generation road groupsets (105 R7100 mechanical, 105 Di2 R7100, Ultegra Di2 R8100 and Dura-Ace Di2 R9200).
Shimano offers 10t sprockets on its 12-speed gravel and mountain bike groupsets (GRX RX820, Deore M6100, SLX M7100, Deore XT M8100 and XTR M9100), however. Therefore, it could decide to implement this technology on a future road bike groupset as well.
If Shimano releases a 13-speed groupset, it appears it would also be 2x compatible, because the patent details a new wireless front derailleur.
Historically, Shimano has not officially supported 1x drivetrains for road bikes, preferring to only offer such setups on its gravel and mountain bike groupsets.
The existence of a potential new front derailleur design doesn’t rule out the possibility of a 1x Shimano road groupset, but it seems to show Shimano remains committed to 2x drivetrains nevertheless.
Shimano jumps on the fully-wireless bandwagon
As well as showing a 13-speed cassette, Shimano’s patent reveals details of a new fully wireless Di2 system.
According to the patent, each derailleur would house its own rechargeable battery.
On the rear derailleur, the battery would be housed within the parallelogram, with the patent appearing to detail more than one possible configuration.
A charging port is potentially located at the rear of the derailleur, in a similar position to current Di2 rear derailleurs, or on the parallelogram itself.
On the front derailleur (Fig. 45 and 47), the battery is located “between an outer link member 30X and an inner link member 30Y of the electric front derailleur” – meaning it would be housed within the main body of the derailleur, alongside the other electronic components.
It’s not clear where the charger port for the front derailleur battery is located, but the patent references a new charger design (Fig. 40 and 41), which could be intended to charge it in situ.
This may suggest the batteries in this system are not removable, unlike on SRAM and Campagnolo’s wireless electronic groupsets.
On SRAM’s AXS drivetrains, each derailleur is powered by an individual SRAM AXS battery – which can be quickly clipped on and off to replace a dead battery.
Shimano may be unable to use such a design due to patents and intellectual property owned by SRAM. Campagnolo’s new Super Record Wireless groupset uses different batteries across its front and rear derailleurs to avoid infringing on SRAM’s patent.
Why go fully wireless?
SRAM paved the way for fully wireless electronic groupsets, with the launch of its first-generation Red eTap groupset in 2015, and Campagnolo has since followed suit with its flagship Super Record Wireless groupset (which launched in 2023).
With the rise of fully integrated front ends on bikes of all shapes and sizes, from high-end aero road bikes down to cheap gravel bikes and even commuter bikes, the desire for wireless groupsets has mounted in recent years to ease installation difficulties.
In contrast to its two major competitors, however, Shimano opted for a semi-wireless approach with its current generation of electronic groupsets.
These see wireless shifters paired to a rear derailleur, which contains the ‘brains’ of the system. This rear derailleur then uses a wired connection to the front derailleur (where present) and a rechargeable battery typically housed within the bike frame.
This enabled simpler and more aerodynamic bike builds than the fully-wired setups used by Shimano’s previous electronic groupsets, although it appears Shimano feels it may be able to simplify things even more.
Certainly, the plug-and-play installation process of SRAM’s AXS groupsets is one of our favourite features – even if fewer riders build their own bikes from scratch nowadays.
Will Shimano bring 13-speed wireless groupsets to gravel and mountain bikes?
Fig. 29 of the patent shows a clutch-equipped derailleur.
These are used for Shimano’s gravel and mountain bike groupsets, suggesting the brand may bring this 13-speed wireless groupset technology to its off-road groupsets.
The same image also appears to show this derailleur is equipped with a SRAM-style universal derailleur hanger.
As we reported last year, Shimano filed a patent showing a rear derailleur fitting directly to a bike’s rear drop-out (held in place by a thru-axle), negating the need for a traditional derailleur hanger.
When will Shimano’s fully-wireless 13-speed electronic groupset be released?
As with any patent application, the language is technical and there’s no indication of whether such a design will see the light of day (we covered a Shimano SPD-SL power meter patent back in 2020, which has yet to materialise, for example).
Shimano, like most other large companies, will routinely file patents simply to protect its intellectual property rights, regardless of whether it intends to bring such innovations to market in the immediate future.
That said, patents can be indicative of what bike companies are working on – patents showing a new SRAM Red AXS shifter design appear to have been confirmed by leaked images of the potential new groupset in recent weeks.
Likewise, 13-speed, fully wireless road, gravel and mountain bike groupsets would certainly be logical next steps from Shimano’s current range of 12-speed, semi-wireless ones.
In the absence of any 12-speed electronic gravel or mountain bike groupsets, perhaps Shimano will even make the leap straight from 11- to 13-speed electronic groupsets for off-road use?
Or perhaps this one is simply still a long way off.
We’ve contacted Shimano for comment and will update this article if we receive a response.