Shimano Ultegra RD-R8150

The Shimano Ultegra RD-R8150 is the central nervous system of the R8100 12-speed Di2 series, delivering the fastest and most precise shifting ever seen in the Ultegra lineup. Following the architecture of the flagship Dura-Ace model, this derailleur now integrates the system's wireless transceiver, charging port, and LED status indicator into a single, sleek unit. With shifting speeds increased by 58% over the previous generation R8050, the RD-R8150 provides near-instantaneous gear changes. Its single-cage design is highly versatile, capable of handling everything from an 11-28T to an 11-34T cassette, making it the perfect choice for both competitive road racing and challenging alpine climbs.

Key Features

• Integrated Wireless Functionality: Houses the "brain" of the Di2 system, enabling wireless communication with shifters and Bluetooth/ANT+ connectivity for the E-TUBE PROJECT app.

• Unified Charging Hub: Features an integrated magnetic charging port (EW-EC300), eliminating the need for a separate junction box and simplifying the cockpit.

• Shadow RD Design: The low-profile silhouette stays tucked under the cassette, reducing aerodynamic drag and protecting the derailleur from impact damage.

• Lightning-Fast Response: Engineered for 58% faster rear shifting compared to the 11-speed R8050, ensuring you never miss a gear during a sprint.

• Single Cage Versatility: A medium-length cage (GS-style) is standard, providing compatibility with high-range 34T cassettes without needing a specialized long-cage version.

Specifications

• Drivetrain Speeds: 12-Speed Di2

• Maximum Low Sprocket: 34T

• Minimum Low Sprocket: 28T

• Total Capacity: 37T

• Pulley Teeth: 11T

• Wiring System: EW-SD300

Typical Components Included

• RD-R8150 Rear Derailleur

• B-Axle Washer

• User Manual

• (Note: EW-EC300 Charging cable sold separately)