Electronic drivetrains require a central processor to coordinate shift commands, and the V4 interface unit handles that communication between Ergopower levers and both derailleurs. Campagnolo's Ergopower levers send analog signals when you press the shift paddles, while the front and rear derailleurs operate digitally. This interface converts those analog inputs into precise digital commands and routes them through the EPS Power Unit to execute each shift. The processing happens thousands of times per second in the background, which is why EPS shifts feel immediate regardless of load or cadence.

The V4 designation marks Campagnolo's fourth-generation interface architecture, and the key upgrade centers on wireless connectivity. Dual internal antennas broadcast via Bluetooth Low Energy and ANT+, which means the interface can communicate simultaneously with bike computers, power meters, smartphones, and Campagnolo's MyCampy app. That app access lets you adjust shift speed, multi-shift behavior, and button assignments from any device without needing a laptop or proprietary dongle. You can also enable automatic shifting based on gear-inch ratios, where the system executes front derailleur shifts automatically once you reach a programmed cadence threshold.

RGB LEDs on the interface body display battery charge level and system diagnostics. Green indicates full charge, yellow signals moderate remaining capacity, and red warns of low battery. If a fault develops, the LED sequence changes to communicate which component needs attention. The interface also processes Zero Setting during initial derailleur installation and Ride Setting adjustments you make while riding, storing those calibration values and applying them automatically.... Read More