This article was produced in association with Parcours
Unbound is 18 and gravel racing has come of age. It is asserting itself with its own community, its own rules, its own culture, its own identity and its own equipment. It doesn’t need to borrow from its parent cycling disciplines any more.
British brand Parcours is at the forefront of gravel racing’s technological breakaway. Parcours has just launched FKT, the first truly aero-optimised gravel wheelset which, for the first time, doesn’t see knobbly tyres as an aerodynamic penalty but instead as an opportunity for optimisation. Designed specifically for a particular type of gravel tyre, Parcours has wind tunnel data to prove that its FKT wheels could save the latest generation of elite gravel racer up to six-and- a-half minutes over the 200 miles of Unbound. That’s the difference between first and 13th place.
In Parcours founder Dov Tate’s words: “If you take our previous generation of gravel racing wheel that people have been racing in UCI World Series, the difference between that and FKT is the same in watt-saving terms as going from a shallow climbing wheelset to a full time trial setup with a disc rear and deep-section front on the road. It doesn’t look like such a change but we’ve got the data to show that it is.”
The FKT has an innovative truncated virtual foil rim profile – more commonly used for frame tubes – that helps manage the airflow coming off the much wider tyres with more extreme tread that are used for gravel. Additionally, the FKT rim is designed around a 40mm gravel tyre with the Panaracer GravelKing X1 tread pattern. According to Parcours, the GravelKing X1 was chosen as the benchmark tyre after extensive discussions with athletes around their race use case.
Prototype versions of the FKT wheels have already been ridden by Parcours athletes Maddy Nutt and Joe Laverick to wins and top 10s in the UCI Gravel World Series. “I’m not saying it’s all down to the wheels,” says Tate, “but it has given their performances a discernible step up – and it’s our biggest ever step forward against the competition.”
Although Parcours was only founded in 2016, the company already has a history of innovation. In 2020 its Strade road wheelset was the first to feature differential rim depths and widths optimised around a 28mm tyre, informed by an analysis of real-world conditions using marine sensors at the front and rear wheels.
Now, according to Tate, the FKT wheelset represents the “next frontier for speed” in gravel racing. “From a design perspective we’ve seen with previous testing on the road that there are small differences in aerodynamic performance due to tread pattern, so intuitively the difference between gravel tyres is going to be much higher. We did some basic simulations on a couple of different gravel tread patterns and we could see there was a big difference.”
Tate continues: “There have been third parties – such as Swiss Side – that have done test data where they looked at the level of knobbliness of a tyre and its impact in terms of drag. But no one has said, let’s reverse engineer this and design something for gravel.”
The next challenge for Tate was to decide which tyre to use for the design process. “We’ve always tried to steer clear of exclusivity from a tyre manufacturer because a rider might have punctured on a particular road tyre on the first ride and sworn off the brand for life. It’s not rational but that’s what people do. But with gravel there was such a performance argument for it that we had to. Panaracer were super open to it, really excited by it and our project coincided with the launch of their X1 tread pattern – and if you look at tyre choice at gravel races they’re almost always top three. So we did a bit of initial work, benchmarking tyre treads, and the X1 pattern turned out to be fast anyway, even though it wasn’t designed as such. The knobbles on the edge of the tread throw off air a little bit more cleanly than others; the side tread is a little bit less pronounced... Panaracer just seems to have got that right.”
The FKT has a hookless rim with a 27mm internal rim width that’s completely ETRTO (European Tyre and Rim Technical Organisation) compliant from a 35mm tyre upwards. Tate explains that this was important after the media coverage of the hookless tyre blowoff that appeared to cause Thomas De Gendt’s crash in the UAE Tour in February and was one of the biggest challenges in the design of the FKT.
“We said we would never just do hookless for the sake of it or because it saves money in production, but in gravel it makes total sense for impact resistance. The corners around the hooks are stress risers that are more likely to crack under impact, whereas a hookless rim is a rigid unit. Also, all of our hookless gravel rims use a slightly softer resin in the rim walls which is more impact resistant. However, as soon as you mention hookless there are all sorts of questions around blowoffs, safety... In gravel it’s not relevant because pressures are lower and tyres are wider, but we still said that whatever we do has to be ETRTO compliant. Some early prototypes were a lot wider internally but we had to shrink them down.
"The external rim width of the FKT is 40mm and the internal is 27mm: we curved the rim inwards, which works nicely since the airflow coming off the tyre doesn’t interact with the rim that high up – it matters much more what you do further down. Other wheel brands have a 42mm external and 32mm in- ternal, which is miles outside of ETRTO guidance, restricting tyre options. Whereas we can come to market and say, do you know what? We’re clean on this. Everything is compatible as long as you follow tyre manufacturer guidance. And it also gives rid- ers the full choice of tyres. Yes, we’ve designed it for the Panar- acer but if you happen to prefer a different tyre, or can’t get hold of a Panaracer, it’s perfectly safe and performs well enough with any other tyre.”
You might say gravel racing has just used its parents’ flaws to make itself stronger. And faster.
