After months of hype, leaks, rumors, and speculation, SRAM’s new Eagle Transmission has officially launched. It’s an entirely new 12-speed electronic drivetrain, free of any wires, derailleur hangers, limit screws, or B-tension adjustments. Three groupsets are being released–XX SL, XX, and XO.
I spent the last 6 months using and abusing the XO drivetrain in and around Bellingham, Washington. During that time period, I racked up over 1,000 miles (1609 km) and 175,000 vertical feet (53,340 m) of climbing over the course of 65 rides. Those miles included lots of rain, more snow than I would have liked, and a healthy dose of magical hero dirt to round things out.
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The video above gives a look at the basics of the new groupset, and goes into my riding impressions. For the full in-depth review and development story, head over to .