Shadow Rear Derailleur (12 speed)
This DURA-ACE Rear Derailleur is likely to be announced by Shimano in September 2021. It'll be a 12 speed system, semi-wireless and use a new battery, the BT-DN300.
This derailleur features a charge port, LED, button and an EW-SD300 type port used to connect the derailleur to the battery. Both the rear derailleur and the front derailleur connect to the battery using a wire. The shift levers send their shift commands to the rear derailleur wirelessly.
The low sprocket maximum is 34T and I expect a lot of bikes to be built up with 11-34T cassettes.
These 12-speed derailleurs use the same charger as the new Di2 power meters, and perhaps even better, the port cover can be replaced when broken.
Details & Specifications
|Shimano model number:||RD-R9250|
|E-Tube Port type:||SD300|
|Component series:||DURA-ACE R9200 (Road)|
|Downloads:||RD-R9250 / RD-R8150 User Manual|