Shimano Dura-Ace RD-R9250 Di2 12-Speed Rear Derailleur

Faster than ever before. The RD-R9250 model not only offers the fastest gear changes on the cassette to date and the largest gear ratio range of a Dura Ace rear derailleur, but can do much more. By integrating the Wireless system and charging port into one compact unit and thus covering a wide range of functions, it practically becomes the heart and brain of the entire Di2 assembly.

The built-in transmitter ensures wireless communication with the STI brake/shift levers ensuring podium-worthy, lightning-fast and precise shifting. Using Bluetooth and ANT+, it is also responsible for data transmission to the E-Tube Project and E-Tube Ride apps as well as to third-party devices.

Besides the charging port, the Top Normal rear derailleur features a button for certain Di2 settings and an LED for status display informing you about battery level, pairing and setting mode, for example.

Technologies:

Shadow RD- With their sophisticated technology, Shimano Shadow RD rear derailleurs are especially intended for more aggressive riding style. Their super low profile design carries many benefits. Thanks to the low profile and a single tension construction, the derailleur does not hit the chain stay in rough riding conditions. The result is smooth and silent performance.