Switching drivetrains or replacing a worn freehub body on Reynolds wheels equipped with Industry Nine hubs requires the correct OEM part to maintain the engagement characteristics and bearing interface that make these hubs perform. This freehub body fits Reynolds Aero line wheelsets from 2017 onward that use the Industry Nine hub platform, including Blacklabel Pro and Aero models. The alloy freehub body slides onto the hub shell and retains the 3-pawl mechanism that delivers 6 degrees of engagement for quick power pickup under acceleration.

Freehub bodies wear over time, particularly the spline interface where cassette cogs bite into the aluminum under pedaling loads. Riders who put in serious mileage eventually see notching on the splines, which can make cassette removal difficult or allow cogs to shift under hard efforts. Replacing the freehub body restores clean engagement surfaces without requiring a complete hub rebuild or wheel replacement. The swap is straightforward for anyone comfortable with basic wheel service, requiring only the removal of the end cap and freehub body followed by installation of the new unit.

Drivetrain conversions represent the other common use case. If you purchased Reynolds wheels with a Shimano HG freehub and later moved to SRAM AXS 12-speed or Campagnolo, swapping the freehub body is far more economical than buying new wheels. The hub shell, bearings, and pawl mechanism remain unchanged while the freehub body provides the correct spline pattern for your new cassette. Confirm your Reynolds wheelset model and hub generation before ordering, as Reynolds offers different freehub bodies for their various hub partnerships. The Hayes/Reynolds support site provides technical service manuals to help identify the correct part number for your specific wheels. Compatible models include the Aero 46, 65, and 80 series in both rim brake and disc configurations from the 2017-2019 era, as well as current Blacklabel wheels using the I9 platform.