RaceFace Trace Boost Rear Disc Hub is a durable, cost-effective MTB rear hub built to handle a wide range of trail demands—from XC mileage to enduro hits and e-bike torque—without adding unnecessary complexity.
With a robust alloy hub shell, smooth-running cartridge bearings, and a steel axle and cassette body for long-term durability, the Trace Boost is a practical choice for riders who want reliable engagement and consistent performance ride after ride.
Boost rear hub platform - Designed for modern MTB rear spacing standards used on many current trail, enduro, and e-bike builds
10-degree pawl engagement - Delivers quick pickup for technical climbing, punchy accelerations, and ratcheting through slow-speed sections
Cartridge bearings - Smooth rolling with sealed bearing durability suited to wet, dusty, and high-mileage use
Alloy hub shell - Keeps weight reasonable while maintaining the strength expected for aggressive trail riding
Steel axle and steel cassette body - Prioritizes durability and wear resistance, especially under higher torque loads
International Standard 6-bolt rotor mount - Straightforward compatibility with common 6-bolt MTB disc brake rotors
Freehub compatibility note - The Shimano/SRAM 8–10 speed freehub is compatible with Shimano 11-speed Mountain cassettes
Specifications & Identifiers
Axle Size
12mm
Bearing Type
Sealed Cartridge
Brake Type
6-Bolt Disc
Cassette / FH Body Type
Shimano HG, Shimano Micro Spline, SRAM XD
Color
Black
Defined Color
Black
Designed for ebike
No
Front/Rear
Rear
Hub Spacing
148mm
Rear Axle Spacing
148mm
Skewer Included
N/A
Spoke Count
32
Spoke Interface
J-Bend
Weight
-
Black - Micro Spline UPC
821973391878
Black - Micro Spline MPN
HUB21T148X32HMSSBLKR
Black - Shimano HG UPC
821973391892
Black - Shimano HG MPN
HUB21T148X32HSHISBLK
Black - XD UPC
821973391915
Black - XD MPN
HUB21T148X32HXDSBLKR
Tree Fort ID:
333222476894
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