Box Components’ Prime 9 Drivetrain

Are fewer gears better for electric mountain bikes?

Is more always better? Box Components founder Toby Henderson doesn’t think so—at least when it comes to gearing for electric mountain bikes. While manufacturers of drivetrain components for traditional mountain bikes keep adding more cogs to their systems (are you ready for 13-speed?), Box has gone the opposite direction in designing its nine-speed Prime 9 wide-range drivetrain for use on eMTBs.

Box’s Priime 9 drivetrain is designed for electric mountain bikes.
Box’s Priime 9 drivetrain is designed for electric mountain bikes.Alberto Beltran

Cycle Volta recently visited Henderson at Box Components’ headquarters in Anaheim, California, to learn more about Prime 9—and to try the system ourselves out on the trails. We found the shifts to be unfailingly precise, and we never wanted for more cogs since pedal assist on the Class 1 ebikes we rode overcame the gear jumps so easily. Click on the video to learn more about Prime 9.

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