We have just received a pair of Rolf’s mid-range Prima VCX disc wheels which are designed to be a versatile wheelset, being rim brake compatible, so in theory could be used on multiple bikes; however, the rear hub is 135mm so that may rule out non-disc road bikes. They are a reasonable weight at 1695g for the pair in clincher format, with the front being 795g and the rear 900g.
Spoke count is the same front and rear at 20 bladed Sapim CX-Speed spokes. Rolf are famous for their paired spokes which they were the first to introduce in 1996. The theory is sound; by fixing the spokes to the rim in pairs, Rolf counter the outward pulling force of each spoke. This allows Rolf to build truer wheels on lighter rims using fewer spokes, which in turn can create more aerodynamic, faster wheels. The wheels also benefit from Rolf’s ‘Dish Reducing Design’ which simply increases the support offered by the drive side spokes to improve wheel stiffness.
The wheels come as alloy rimmed tubular or clinchers. The clincher version rim we have has a 33mm deep and 22mm wide rim, with ‘Delta Rim Technology’, which apparently takes it’s cue from skydiving where the ‘Delta track is the fastest position for gaining forward airspeed’. Rolf’s Delta rim profile uses the increased width and sidewall shaping to improve airflow and stability in both head-on and crosswinds. As we’ve heard from lots of manufacturers, as well as speed gains you get improved cornering and handling from better tyre shape and support.
The hubs are Rolf’s own CNC machined XST+ units with steel bearings and, as already mentioned, 135mm spacing at the rear with a 3 pawl titanium freehub for Shimano/SRAM 10 or 11-speed. A 15mm thru axle is available as an option upfront but they come with steel quick release skewers as standard. Rolf’s ‘Differential Flange Diameter Technology’ is basically an oversized non-drive side flange, which Rolf claim ‘provides the leverage to transmit drive torque in the rear wheel to the non-drive spokes, thereby increasing the number of torque absorbing spokes’. We’ll take their word for it, though it must work as it is similar to that we’ve seen on many other wheels before, such as Fulcrums where it was pretty effective.
Obviously at this time of year we are thinking of these in a cyclocross context and so they are off for review with the boys on the disc bikes, who will follow this up with a full review soon.
Rolf Prima VCX Disc RRP £899 / $1099.