Shimano SM-EW90-B Junction A
Best essential component for reliable electronic shifting system integration.
This essential junction box cleans up the cockpit by consolidating electronic shifting wires under the stem. It simplifies system management by providing a central charging point, battery status monitoring, and easy gear indexing in one compact, lightweight unit.
$139.50
More Di2 options
Shimano SM-JC40 Di2 External Frame Junction Box
$28.99
Shimano Di2 Junction Box
$139.99
Shimano Di2 Junction Box
$31.99
Shimano Di2 Battery Mount
$154.99
Shimano BT-DN110A-7 Di2 Internal Battery
$170.00
Shimano Di2 E-Tube Wire
$30.00
Shimano BT-R1A Di2 Battery
$99.99
Shimano JUNCTION-B
$31.00
Shimano EW-JC200
$25.99
Shimano EW-JC130
$57.60
Shimano Di2 Battery Mount
$84.99
Shimano BCR1 E-Tube Battery Charger
$21.54
Shimano BT-DN320A Battery
$55.00
Shimano SW-RS910 Di2 Junction Box
$21.99
Shimano Di2 Battery BT-DN320
$55.00
Shimano E-Tube Y-Splitter
$52.53
Shimano EW90-A Di2 Cockpit Junction Box
$140.00
Shimano EW90-B Di2 Cockpit Junction Box
$181.32
Shimano EW-WU111 Wireless Unit
$75.00
Shimano SW-EW90-A
$117.00
Shimano SM-JC41 Di2 Junction Box
$38.00
Shimano EW-SS302
$25.99
Shimano Di2 E-Tube Wire Cover
$15.00
Shimano Di2 eTube EW-AD305 Conversion Adapter
$23.99
Shimano Di2 E-Tube Y-Split Connector
$54.99
Shimano Di2 E-Tube Battery Mount BMR2
$99.99
Shimano ST-R785 Di2 Shift/Brake
$259.99
Shimano BMR1 and BRM2 Di2 External Battery Mount Base
$47.22
Shimano Power Cable
$14.00
Shimano BT-DN110-1 Di2 Battery
$159.99
Shimano EW-SS302 eBike Sensor Unit
$27.90
Shimano SD50 E-Tube Wire Cover
$15.00
Shimano BM-DN100-L Di2 Battery Mount
$130.98
Shimano Di2 EW-SD50 E-Tube Wire
$30.60
Who it's for
- Cyclists desiring extensive electronic shifting customization and accessory integration.
- Riders prioritizing a tidy bike aesthetic and efficient cable routing.
- Performance-oriented cyclists seeking flawless and dependable gear changes.
- Users who value quick troubleshooting and monitoring of their electronic drivetrain.
Who should skip it
- Budget-conscious cyclists or those upgrading from mechanical systems.
- Riders with non-Di2 setups or those considering other electronic groupsets.
- DIY mechanics new to electronic shifting or seeking simple installations.
Performance breakdown
Cockpit Integration
Under-stem mounting keeps cables tidy for a clean, professional aesthetic.
System Expandability
Five ports offer ample room for additional shifters or accessory integration.
Maintenance Accessibility
Dedicated charging port makes system updates and battery management straightforward.
Diagnostic Clarity
Integrated LED indicator provides immediate, reliable feedback on battery status.
Build Durability
Robust construction withstands the elements and frequent cockpit adjustments.
Setup Simplicity
Indexing switch allows for quick, precise gear adjustments on the fly.
Key Specs
Model Number
SM-EW90-B
Series
DURA-ACE 9070
Weight
13 grams
E-tube ports
5
Charging ports
1
Compatible electric wire
EW-SD50
Mounting position
Under stem
Type
External
Compatibility
Di2 Electronic Shifting
Quantity Per Pack
1
Know before you buy
Still have a question?
Ask Metto anything about the Shimano SM-EW90-B Junction A before you decide.
