Having just rebooted the brand with new mountain bike hubs, Project321 was showing off a slightly quieter version for gravel bikes at the 2024 Sea Otter Classic.
As Lightning McQueen learned, sometimes you need to go slow to go fast, and that’s the thinking behind the gravel hubs. Project321 has trimmed back the number of pawls inside the hub, which slows down the engagement slightly but makes it quieter and infinitesimally reduces drag.
The big difference between the mountain bike hubs, which have eight pawls working in pairs of two, is the halving of of the pawls to four. This increases the engagement from 1.25º for the MTB hubs to 2.55º for gravel, with an effective 144 points of engagement.
Two pawls remain engaged at all time, with the other two phased by half a step to engage next. That’s still really quick, especially for gravel (or road) where you’re maintaining a constant cadence. The pawls are magnetically pulled into engagement, so there are no small springs that can pop out during servicing.
The hubs place two double-row bearings at the edges of the freehub body, typically the point experiencing the highest torque and sheer forces.
They use their same 6-Lock rotor rings, letting you run 6-bolt or Center Lock rotors on the same hub. They’re natively Center Lock, but use a lock-ring style attachment to fix 6-bolt rotors to them. Launch date and pricing TBA.