Description
A 55mm carbon disc rim at £150 invites scepticism. The construction background is worth understanding before dismissing it.
This rim is made by Stren, a Chinese manufacturer with an extensive history producing carbon rims for major brands. It is built from Toray T700 carbon fibre using a slit tape filament winding process, and that manufacturing method is worth a moment’s explanation because it is less familiar than pre-preg despite being, in several meaningful respects, its natural successor.
Carbon rim construction has gone through broadly three generations. The earliest approach used dry carbon fibre with resin applied by hand. This was effective, but highly dependent on the skill of the laminator and inconsistent in resin distribution. Pre-preg addressed this by impregnating the fibre with resin before layup, producing much more consistent results and becoming the dominant method for higher-end carbon components. Filament winding goes a step further. Rather than laying up sheets of material by hand, a machine winds continuous carbon tows around a mandrel in precise, controlled patterns. Slit tape winding uses narrower, more accurately placed tows than conventional filament winding, producing even better fibre consolidation, more consistent resin distribution, and longer, less interrupted fibre paths through the structure. The process is machine-executed throughout, which removes the variability that hand layup, however skilled, inevitably introduces. The analogy to hand looming versus machine looming is reasonably apt: both can produce good cloth, but the machine produces it more consistently. A number of high-end rim manufacturers now use slit tape filament winding. We are not in a position to name them, but the process is not a cost-cutting measure.
The practical result is a rim that is notably robust for its weight class. At 480g it is not the lightest 55mm carbon rim available, but it is built to a consistency and impact resistance standard that lighter, hand-laid rims do not always match. Filament wound rims handle incidental impacts; road debris, potholes, the minor indignities of everyday riding, with less drama than more fragile constructions, which matters on a rim you are actually going to use rather than save for best.
On the profile
At 55mm deep with a 21mm internal and 30mm external width, this is an aero rim in the proper sense. The depth delivers genuine aerodynamic benefit at sustained road speeds, and the 30mm external width suits the tyre-to-rim relationship that modern aero profiling requires. Optimal tyre pairing is around 25mm, though 23-32mm works well across the range. It is a rim for flat to rolling terrain and steadier conditions; the crosswind handling caveats that apply to any deep rim apply here.
Tubeless ready with a hooked bead seat, compatible with standard tubeless tyres without the pressure or compatibility restrictions of a hookless rim.
A note on the build
Paired with the BX822 centrelock hubset this makes a capable, economical aero road disc wheelset. The BX822 accepts any 48-point freehub body, keeping XDR and Microspline compatibility open for the future. A carbon aero wheelset built to this specification, from components with this supply chain pedigree, at this price point, is a straightforward proposition.
The two year warranty covers manufacturing defects.
