The SL-K’s 51mm deep carbon tubular rims have a wide 23mm tyre bed for aero efficiency and handling stability. The shape is somewhere between sharp, knife-like rims and the bulbous Zipp Firecrest style, and gave a good account of itself throughout a blustery ride, with decent ride quality, snappy acceleration, excellent braking in the wet and no nasty surprises.
Light SL-K hubs with two front and four rear sealed cartridge bearings spin smoothly, and combined with the wide rims, increase lateral stiffness and cornering confidence up front, while the narrow rear hub has minimal dishing, creating a responsive wheel with no spoke wind-up under acceleration.
We had trouble inserting the tyre valve due to the deflated bladder inside the rim fouling the holes, which may account for the weight without skewers of 1,580g being 130g above FSA’s listed mass.
This article was originally published in Triathlon Plus magazine, available on Zinio.