British wheel brand Parcours has launched its Strade wide wheelset. The new wheels feature all-new differential front and rear rim profiles. They are ‘aerodynamically optimised for 28mm tyres giving superior rolling resistance, comfort and ride quality without sacrificing outright speed.’
Parcours spent 12 months in partnership with the sports engineering department at Nottingham Trent University developing its new disc-specific, tubeless-ready Strade wheelset.
The company conducted an analysis of real-world wind conditions and the impact of yaw angle on wheel design. The result was the Strade, billed as a next-generation wheelset designed around a 28mm tubeless tyre, which has not only front and rear-specific rim depths but also different rim widths.
In recent years, Parcours adds that bicycle wheel designers have concluded that aerodynamic stability is everything. If the airflow does not stay attached to a wheel, in particular at higher angles of yaw – for example, in crosswinds – it becomes unstable and the turbulence results in increased drag.
Widening the rim begins to solve the problem; but with the Strade, Parcours argues that it has taken aerodynamic stability to the next level.
Collecting wind angle data from sensors located at both front and rear wheels, Parcours found that the average yaw angle at the front wheel was consistently higher than at the rear. This was due to airflow at the rear wheel being affected by the front of the bike and rider interaction (predominantly legs, feet and pedals). Additionally, crosswind handling performance at the rear wheel was found to be significantly less important since the wheel is not free to move on its axis for steering.
So for the Strade front, Parcours developed a wide, U-shaped rim designed for higher yaw with a depth of 49mm and an external width of 32mm; while the rear has a narrower, sharper, V-shaped rim with a depth of 54mm and a width of 30.5mm, which is claimed to be better suited to lower yaw angles.
Parcours ran an iterative CFD design process and then validated the prototypes at the A2 Wind Tunnel in North Carolina. Outperforming the brand’s existing Passista Disc by a wide margin in terms of aerodynamic performance and crosswind side force, the wind tunnel data showed that the Strade, fitted with a 28mm tyre, is’ the new benchmark for a mid-depth, disc-brake wheelset.’
The Strade wheelset runs on Parcours’ precision-machined alloy hubs, which are fitted with high-grade EZO cartridge bearings and use a Centerlock disc fitment. The hubs are fitted for 12mm thru-axles front and rear (adapter kits are available for other axle standards).
Parcours uses Sapim CX-Ray aero spokes, 24 front and rear in a 2-cross pattern.
Parcours Strade specification
Weight: 1,520g (front 690g, rear 830g)
Rim depth front: 49mm
Rim depth rear: 54mm
Max external rim width front: 32.0mm
Max external rim width rear: 30.5mm
Internal rim width (front and rear): 22.5mm
Spokes: Sapim CX-Ray 24 front, 24 rear
Hubs: Parcours Disc
Dov Tate, founder of Parcours, said “With the shift in tyre and braking technologies, we set out to create a new-generation wheel that maximised the aerodynamic and handling improvements of a wider rim and tyre. The result was the super-fast, super stable Strade, which exceeded our project goals and sets a new benchmark in the mid-depth disc wheel category.”