Previous Di2 models were introduced as follows, 10 speed (2009, 7970), 11 speed (2012, 9070), 11 Speed (2016, 9170) and such new tech comes first to DuraAce.
These diagrams, above, are of Shimano’s new rear derailleur for 2021. They come from a public FCC report which has invoked a confidentiality clause on some items until 26 July 2021 (those have not been leaked). Other documents filed here give more clues. From all this documentation we get the following:
- FILING INFO: Whilst only a pre-production unit, it is stated to be representative of the product to be later sold.
- FILING INFO: It’s a rear derailleur, model number 3GK1 (Existing wired Di2 DuraAce derailleur is sold as RD-R9150, 3GK1 are random numbers as allowed by FCC)
- FILING INFO: Mention is made of RD-9250 in the filing.
- FILING INFO: It contains a 7.4V battery. It is not wired to a battery and is independently powered with this battery.
- SPECULATION: There seems to be no obvious indication from the diagram if the battery is replaceable or integral.
- FILING INFO: This pre-approved BLE/ANT+ module forms part of the new rear derailleur
- FILING INFO: It communicates over Bluetooth Low Energy and ANT+
- SPECULATION: Effective use is ANT+ only with BLE for configuring via the Shimano E-Tube app.
- INFORMATION: Previous filings by Shimano do not include a rear derailleur (they were not wireless and I assume the wired derailleurs did not need certification)
- CONCLUSION: This is a wireless rear derailleur
- SPECULATION: likely a new Dura-Ace rear derailleur, retail coding Shimano RD-9250
- FILING INFO: It will be released on or about 26 July 2021
It’s either an 11-Speed or 12-Speed wireless Shimano Dura-Ace rear derailleur RD-9270 for release in summer 2021 to celebrate the approx. 100th anniversary of Shimano’s founding in February 1921.
I’m guessing it will come with other bits too 😉
More Info: I’ve covered this earlier and in more details here, Shimano Dura-Ace for 2021