Shimano Dura Ace EW90 E-Tube battery Connector

SHIMANO Dura-Ace SM-EW90-B E-Tube 5-Port Junction-A: The Command Center for Your Di2 System

Elevate your cycling experience to the pinnacle of performance and integration with the SHIMANO Dura-Ace EW90 E-Tube Junction-A. This essential component is the central nervous system of your Shimano Di2 electronic shifting system, acting as the primary interface between you and your drivetrain. Designed for a clean, professional cockpit, the SM-EW90-B mounts discreetly beneath your stem, consolidating control and information into one sleek, accessible unit. It is the definitive choice for cyclists who demand flawless shifting, effortless system management, and a minimalist aesthetic.

The primary benefit of the SM-EW90-B is its role as a centralized hub. It eliminates the guesswork and complexity of managing your electronic groupset. With a quick glance, you can check your battery status, and when it´s time to recharge, the integrated charging port means you never have to remove the battery from your bike. This junction box also serves as the gateway to fine-tuning your shifting performance, allowing you to enter adjustment mode to perfectly align your derailleurs for crisp, immediate gear changes every single time.

Key Benefits:

* Centralized Cockpit Control: Consolidates the connection points for your shifters and provides a single, easy-to-access interface for charging, battery status checks, and derailleur adjustments.
* Effortless System Management: Features an intuitive multi-color LED indicator that provides an immediate, clear reading of your remaining battery life, ensuring you´re never caught without power. The built-in charging port offers ultimate convenience.
* Professional & Clean Aesthetics: Its low-profile design is engineered to mount neatly under the bicycle´s stem, creating an uncluttered and aerodynamic cockpit that complements the clean lines of modern road bikes.
* Full Customization Potential: Acts as the PC linkage device, allowing you to connect your Di2 system to the SHIMANO E-TUBE PROJECT software. This enables you to update firmware, diagnose issues, and customize functions like shift button mapping and multi-shift speed.

Main Features:

* Features five E-TUBE ports for comprehensive connectivity, typically for left and right shifters, a downtube wire to Junction-B, and two additional ports for sprinter or climbing shifters.
* An integrated, easy-to-read battery level indicator light.
* A built-in, protected charging port for the internal Di2 battery.
* Provides access to the derailleur adjustment mode for precise micro-tuning.
* Compatible with a wide range of Shimano Di2 electronic groupsets.

Cables

The SHIMANO EW90 Junction-A is the master connection point for the E-TUBE wiring system in your cockpit. It requires Shimano SD50 E-TUBE wires (sold separately) to connect your dual control levers (shifters) and any auxiliary satellite shifters to the rest of the Di2 system. The 5-port design provides ample flexibility for complex setups, including time-trial or triathlon configurations. By routing all cockpit cables to this single point, it dramatically reduces cable clutter, simplifying installation and maintenance while achieving a professional, integrated look.

Technical Specifications

Brand:- Shimano.

Category:- Electronic grouspet spare parts.

Specifications:

- Control unit/Junction-A SM-EW90-B 5-Port.
- Model Number: SM-EW90-B
- Series: Dura-Ace 9070
- E-TUBE Ports: 5
- Function: Junction-A (Primary cockpit control and interface)
- Mounting: Under-stem strap type
- Compatibility: Shimano E-TUBE Di2 Systems (Dura-Ace, Ultegra, etc.)
- Functions: Battery Level Indicator, Charging Port, Gear Index Adjustment, PC Linkage Port