British wheel innovators Parcours has unveiled its new gravel race wheelset with the daring declare of being a primary of its type.
“The FKT wheelset is the primary actually aero-optimised gravel wheel. Moderately than trying to mitigate the aerodynamic penalty of a gravel tyre, the FKT is all about optimising efficiency in gravel racing,” the model states, backing up its claims and findings by releasing a white paper of its design philosophy, course of and wind tunnel testing.
In its white paper, the model concludes that in relation to successful gravel races, aero is certainly all the pieces.
“It’s clear to see that there are substantial aerodynamic efficiency advantages out there to a gravel racer,” it states. “To place the scale of the profit into perspective, the efficiency good thing about FKT over a earlier era of gravel race wheel is much like shifting from a low-profile climbing or coaching wheel on a time trial bike to a full race setup of deep-section entrance and rear disc wheel.”
Nonetheless, the tyre-and-wheel pairing performs a serious position. Thus, Parcours particularly designed the FKT wheel round Panaracer’s new Gravelking X1 tyre in 40mm width. Parcours shouldn’t be distinctive in recognising the significance of how a tyre profile and rim work together in relation to aerodynamics. And we’ve been seeing a rise in partnerships between wheel and tyre producers (i.e. DT Swiss and Continental) or wheel manufacturers bringing their very own tyres to market (i.e. Enve)
Parcours estimates, primarily based on its research, that utilizing the FKT wheelset paired with GravelKing X1 tyres would save practically 12 minutes over a earlier era gravel wheel paired with the next tread tyre on the 200-mile Unbound occasion. At this yr’s race, that point distinction would have been the distinction between a primary and a Sixteenth-placed end within the males’s race, or the primary and Fifteenth-placed finisher within the ladies’s race.
“The efficiency good thing about an aerodynamically-optimised gravel bike can’t be underestimated,” Parcours concludes.
The most recent race content material, interviews, options, opinions and professional shopping for guides, direct to your inbox!
With regards to successful gravel races, aero is all the pieces
The Parcours FKT wheelset noticed at Unbound Gravel in June
(Picture credit score: Anne-Marije Rook)
The expansion and professionalisation of gravel racing is pushing the innovation of off-road merchandise to be quicker and extra environment friendly. With riders now tackling 200–mile course in a bit over 9 hours, velocity is of the utmost significance and inevitably, the focus turns to aerodynamics.
Parcours already catered to the journey aspect of gravel using with its Alta wheelset, however when its sponsored athletes got here searching for methods to optimise their setups, the engineers –already skilled in aerodynamics– started working.
Nonetheless, it rapidly grew to become clear that designing for aerodynamics on the highway and gravel are vastly totally different.
For one, Parcours designed its highway wheels across the philosophy that the optimum rim width needs to be barely wider than the tyre width. With 40mm+ tyres being the norm in gravel, nonetheless, the ensuing tremendous broad rims would necessitate extra materials, which in flip means added weight, detracting from the aero advantages. Moreover, wider exterior rims make it difficult to keep up an inside rim width compliant with ETRTO tips.
Concerning rim depth, Parcours’ earlier research discovered that the perfect rim depth-to-tyre width ratio began displaying diminishing returns at >4:1 (depth:width). Utilizing a 28mm tyre as a benchmark on the highway led to the creation of the Chrono Max, the model’s quickest wheel, which options an 83.6mm rim depth. Nonetheless, for gravel tyres of 40mm+, this may suggest a complete rim depth of 120mm+, which might, once more, add weight and negatively have an effect on bike dealing with.
However maybe the best problem was contemplating tread patterns and their intensive variations.
So, with these challenges in thoughts, Parcours established design parameters:
- Most exterior rim width set between 40-45mm for body clearance.
- Inside rim width set to 27mm to accommodate a variety of tyre widths.
- Utilising a hybrid Kamm tail design to steadiness aerodynamic advantages and sensible rim depth.
- Optimising the design round one particular tyre tread quite than tyre width. Parcours selected the Panaracer GravelKing X1 for its all-roundedness and a steadiness of aggressive tread with a low rolling resistance.
- Driving circumstances. Parcours states that real-world wind knowledge indicated that, in gravel racing environments, there’s a considerably decreased distinction in yaw circumstances – the angle between the path of the wind and the bike’s ahead movement– in comparison with highway racing.
Prototypes had been designed utilising NACA airfoil profiles and 3D CAD modelling and examined utilizing laptop simulations (Computational Fluid Dynamics). Last designs underwent testing in North Carolina’s A2 Wind Tunnel in opposition to a competitor, different Parcours wheel fashions and totally different tyre profiles.
Right here, the FKT proved considerably quicker than the model’s Ronde wheelset in addition to the favored Zipp 303 Firecrest wheelset, each fitted with the identical X1 tyre on the similar tyre stress.
(Picture credit score: Parcours)
What intrigued the take a look at crew most was the affect of tyre selection and tyre-wheel mixtures.
“Selecting to run a 45mm GravelKing X1 over a 40mm GravelKing X1 would result in an estimated time penalty of two minutes 36 seconds at Unbound Gravel,” the crew concluded. “Nonetheless, with the related enchancment in traction and management, in some circumstances and for some races this will change into the popular setup.”
Evaluating the Panaracer GravelKing X1 with different widespread fashions revealed extra substantial variations.
(Picture credit score: Parcours)
“The extra pronounced tread on the “Excessive” tread tyre examined the slowest, while there was a fabric distinction in efficiency proven by the “Low” tread tyre. Regardless of this, the GravelKing X1 remained by far essentially the most aerodynamic tyre when fitted to an FKT wheelset,“ testing concluded.
As famous earlier, Parcours’ research underscores the significance of tyre and rim compatibility, particularly within the gravel aspect of issues.
The Parcours FKT Wheelset
Parcours FKT wheelset on a Specialised Crrux
(Picture credit score: Parcours)
The ultimate product has already secured wins and High 10s within the UCI Gravel World Collection and a podium on the Migration Gravel Race by athletes Maddy Nutt and Joe Laverick.
The FKT wheels function a hybrid, truncated digital foil form, meant to handle airflow from a wider tyre, decreasing turbulence attributable to the non-slick tread sample required for gravel using. And in contrast to Parcours’ aerodynamic highway wheelsets, the FKT wheelset encompasses a symmetrical entrance and rear rim.
The FKT encompasses a hookless rim with a 27mm inside width and is ETRTO compliant from a 35mm tyre width upwards. It additionally incorporates the identical IMPACT+ know-how seen in Parcours’ present Alta rims, which makes use of a extra versatile resin on the rim edge to extend sturdiness and affect resistance.
The hubs used within the FKT are the identical as present in Parcours’ highway disc fashions, with a drive mechanism that features a 6-pawl freehub operating on a 44T ratchet ring.
FKT wheels can be found for pre-order by July for supply in August. All wheelsets ordered throughout the pre-order interval will embody a pair of Gravel King X1 tyres.
Particulars:
- Worth: £1,199 / $1,599 / €1,559
- Weight: 1,500g
- Rim depth: 47.0mm
- Max rim width: 40.0mm
- Inside rim width: 27.0mm
- ETRTO compliant with 35mm+ tyres
