Materials
Our in-house engineers utilize FEA software to digitally shift material from low stress areas to higher stress areas resulting in a lighter weight, robust and durable straight-pull hub shell. HUNT Sprint SL hubs start as a block of aerospace grade 6066 alloy. After cold-forging and pressing the material into the rough hub shape, this process aligns the grain structure and reduces machining time and waste, they go through a T6 heat treatment to make them stronger.
The hubs are then machined and anodised, before machining again, to get the bearing faces to the required tolerances. Within the shell, we use a 15mm diameter axle made from 7075-T6 alloy, offering incredible yield strength and UTS (Ultimate Tensile Strength).
Bearings
The Sprint SL hub system features four bearings in the rear hub and two in the front, each spaced as far outboard as possible in the shell for lateral rigidity. We offer riders multiple high performance bearing options to best suit their terrain, riding conditions, and preferences.
Freehub Details
For our freehub systems, we strive to deliver the features that matter most to the rider. We utilize a tried and true, easy to maintain design that is constructed of 7075-T6 alloy. The mechanism consists of a leaf-sprung, three-pawl driver, with three engagement teeth to each pawl, meshes with a 48-tooth steel outer drive ring that is threaded into the hubshell. he system provides 9 points of contact with an engagement angle of just 7.5°. For the rider, this system transfers pedaling input immediately, whether you’re powering up a steep climb or sprinting through the final turns of a criterium. There is also a Steel Spline Insert re-enforcement to provide excellent durability against cassette sprocket damage often seen on standard alloy freehub bodies.
Same Performance, Less Noise
Our hubs have a brilliant, yet subtle buzz when coasting. A lot of variables can affect the acoustics when you begin to coast, including the volume of air space in the hub, the thickness of the hub shell, the number of engagement points, the stiffness of the leaf springs, the level and type of lubrication, as well as the speed at which you are coasting. Based on rider feedback, we have refined our “buzz” with a set of pawls installed with slightly rounded off tips and also a set of leaf springs which have a softer preload. The result is a quieter, but not silent, ride when you begin coasting. (Learn more about freehub sound from the experts at GearPatrol).
Proven in Competition
Sprint SL hubs have sat at the heart of our road performance wheels for years, and have been validated at every level of racing, including Grand Tour stages victories, one-day classic podiums, national titles, countless classification jerseys, and all types of racing in between.