Let's say I have a 9170 Di2 11 speed group and want to update to 9200 12 speed keeping what I can. That means a new RD, battery and wires are a must. Shimano claims the old 11 speed Di2 time trial shifters will be compatible, with an adapter, but what about ST-R9170 and other 11 speed Di2 shifters, are these compatible too? Did anyone try yet?

  • Can somebody enlighten me: Gear shifts come with I2C buses and batteries these days? ("If every toaster is a computer, every toaster can crash.") Sep 1, 2021 at 10:22
  • @Peter-ReinstateMonica Shimano Di2 has been available since 2009. Latest SRAM road groups are electric only, 9200 and 8100 are too. Sep 1, 2021 at 12:40

3 Answers 3


Update December 23, 2021

Shimano have given me a media bike to use for a month, so I thought I'd connect some of my old levers, to prove what I wrote below.

I first disconnected the front derailleur, then connected an EW-AD305 to that, and used that to connect an SM-JC41 (using EW-SD50).
Then I connected my SM-PCE02 to the SM-JC41 and made sure E-Tube Project V5 gave the OK :).

At this point the bike still shifted, of course - you don't need a front derailleur to build a working Di2 bike.

Di2 components and laptop, ready to go

I then connected my ST-R8070 (11sp Ultegra Di2 lever) to the same SM-JC41:

ST-R8070 connected

Now.. when I pressed any button on any shift lever, the bike wouldn't work. No movement or LEDs at all. It was pretty much dead, even when using the 12-speed lever.

When I ran E-Tube Project V5 again, it connected to the bike, but immediately disconnected. It complained that the bike setup was incompatible, as described in my original answer below.

No, you really cannot mix 11-speed and 12-speed levers

So.. no - you really cannot mix these. Of course, trying this was pretty much an exercise in futility, but since you wanted proof, here it is :).

original answer:

The answer is no, you cannot use any of your older shifters, unless they're one of these time trial shifters:

  • ST-R9160
  • ST-R9180
  • ST-R8060
  • SW-R9160

or the satellite shifter:

  • SW-R9150.

Shimano has not given any of the other older components the firmware updates required to work with the 12-speed components. While you can connect those components using the EW-AD305 adapter, they simply won't work. It's not that the EW-SD300 wire 'protocol' is different - the wiring is actually exactly the same, but smaller. (you can use EW-AD305 and EW-SD300 to connect 11 speed components to other 11 speed components no problem, for example)

So why is there no firmware update for the other older components? As far as I know Shimano want to say goodbye to the EW-SD50-wired components. They don't want to have to support ST-6770 for the rest of the Di2 lifetime. And while that sucks for those of us wanting to 'easily' and cheaply upgrade to the 12 speed system, I get it. The EW-SD50 wires are bulky and I very much prefer the EW-SD300 wires. Also, I would hate to still see EW-SD50 components on 'new' bike builds years from now.

One could argue that they could drop support for 10-speed components and just roll out firmware updates to 11-speed shifters, but you have to draw the line somewhere and they did.

As for why they have published firmware for the units I mentioned above:

The TT-Di2 market is relatively small. At the moment it's not feasible to make new EW-SD300 versions of those shifters for just a handful of riders, so Shimano updated the firmware on those components instead (and let them work with the 12-speed stuff).

The SW-R9150 is a satellite shifter, but the reason for that being compatible is simple: some people want more than two satellite shifters. 12-speed Di2 satellite shifters use a special plug and connect to the dedicated satellite shifter port on the shift levers. Each lever has one EW-SD300-Satellite port and one regular EW-SD300 port (two in case of rim brake). That means that you can only install one pair for EW-SD300-satellite shifters. If you want more, you'll need to use SW-R9150 + the EW-AD305 adapter.

To summarize:
The new / old wiring is exactly the same. There is no problem there. The older components have not gotten the firmware update "Adapted for new DURA-ACE R9200 Series and ULTEGRA R8100 Series." and will therefore not work with the newer series.. except for the ones I listed at the top of this answer.


  • Did you try this yet? One of the aspects I am interested in is how thing actually work instead of what the manufacturer says. For example, what happens if you splice the wires? Are protocols really different? Sep 20, 2021 at 2:32
  • Fair point, and I haven't had a chance to play around with this yet. However: while the wiring is exactly the same (like I said, you can use EW-SD300 on an 11 speed bike if you like), it won't work. Shimano have updated the firmware for those units I listed to make them work with the 12 speed systems. If that wasn't necessary, they wouldn't have done it. The other units did not get an update. Look for "Adapted for new DURA-ACE R9200 Series and ULTEGRA R8100 Series." on the E-Tube site bike.shimano.com/en-EU/e-tube/project/firmware.html Sep 20, 2021 at 7:10
  • Yeah, I am aware of what Shimano says. Thanks for the answer anyway, upvoted, but I am going to wait for a more comprehensive one (or an update to an existing one) before accepting. Sep 20, 2021 at 9:17
  • 1
    So, there it is - I've tried it :) Dec 23, 2021 at 16:13
  • @Klaster_1 this is basically the update to my existing answer. I would vote for this.
    – Weiwen Ng
    Dec 23, 2021 at 16:44

From what I can see, the answer is no, at least directly. Shimano has made a new standard for the E-tube wire which is thinner and sleeker, but also has a new, smaller connecter. The new cable physically won’t connect to the old shifters.

Whether or not adaptors will be available from Shimano or others is something I can’t answer at the moment.

  • 1
    It’s also not just a simple two wire button. As far as I’m aware it’s a bus (like I²C) and it’s unlikely they’ll be compatible.
    – Michael
    Sep 1, 2021 at 6:52
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    The EW-SD300 E-tube wire standard used by the R9200 and R8100 groupsets isn’t new, it came out with the EP800 E-MTB groupset in August 2020. And yes, there is an adapter, the EW-AD305, but (as with many bicycle components at this current time) good luck getting hold of one right now. And yes, Di2 uses an interface based on the automotive CANbus, and has done for years, but given the existence of the adapter, R9100 and R9200 should be electrically compatible. Hopefully people like GPLama will test this when they get their hands on R9200/R8100. Sep 1, 2021 at 9:40
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    @user7761803 Ah, did not know that. Di2 is a bit too far outside my budget to be concerned with its operation :) My information about the cable being different from the R9170’s is correct though, right?
    – MaplePanda
    Sep 1, 2021 at 14:55
  • 2
    @Michael Surely some kind of junction box that interprets one protocol’s input and spits out another protocol’s output can exist. Bicycle shifters aren’t exactly a very high bandwidth application I think. And look, the EW-AD305 exists!
    – MaplePanda
    Sep 1, 2021 at 14:56
  • 1
    @MaplePanda the cables are thinner, the connectors are different, but the electrical signals are the same (to the best of my knowledge) hence a passive adapter exists (assuming it's passive given it's similar in cost to the cables themselves!) Sep 2, 2021 at 14:50

Nobody has tried yet, but it's likely that some people will, one of them being Terry at Bettershifting.com.

As background for other readers, the Di2 system battery contains the central processor. Shimano just announced 12s Dura Ace and Ultegra groups today. Time trial and triathlon bikes are a very small share of the performance bicycle market. Shimano appear to not have developed new 12s components. They instead developed an adapter box (component AD-305), which you can plug your 11s TT components into, and which is then wired to the new Di2 battery. This is discussed in this Cyclingtips article.

I don't have an intimate knowledge of Di2, but my understanding is that Shimano would need to issue firmware to enable the older TT shifters to talk to the adapter box. This comment on the article speculated that they might not do so for older road shifters. Indeed, a Shimano representatives discussed on various later podcasts that they would not do so. I think I recall that at one point, older 10s Di2 shifters would work with an otherwise 11s Di2 system, but Shimano disabled that functionality in a firmware update. Basically, it could be done, but Shimano judged the effort to reprogram the firmware not to be worth the effort. A harsher way to view this is as an anti-consumer decision.

  • 1
    hah, thanks! I'll try it some day, but the way things are now, it's not going to work :) Sep 19, 2021 at 20:31

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