The engineer at YT since the very beginning, Stefan Willared has masterminded some of our favourite bikes over the years. His latest project has been to deliver Gwin an ultimate racing machine in the latest iteration of the Tues.

Gwin and the Mob team have been the main shapers of the direction of the bike and Stefan and his team have simply worked to deliver the bike he needed. We caught up with Stefan in Losinj, where his bike had already won a World Cup before its official unveiling, to chat through the development process with the world's fastest downhiler. 

How long has this been in development with YT

Around about two years. So the redevelopment time from the first modification ideas to doing sketches, going into the kinematic simulations, discussing with the team, discussing with riders, sharing ideas until the final mass production is about two years.

So is it because Gwin came on board or is that coincidental?

When he came in, we already had the plan to design a new bike. He started racing the Fontana races and the first World Cup races and we started checking the real decisions he creates on the bike. How deep is the fork inside the crowns? What kind of handlebar rise is he riding, up sweep, back sweep? What does that mean for the bike?

So was cockpit really where his feedback was focussed?

For sure, the riding position is one of the key factors for everybody. We need to feel comfortable on the bike, that's the main point. We were really close to perfect but he's not the guy, and we are not the development guys, to say: "oh, it's fine", we try to develop, to reach the next level.

This was a really nice combination between the YT development department and the Mob racing team. It was not only Aaron Gwin, for sure, Aaron had the most impact, but also the mechanics, the influences and things we put into the bike, there's a lot of feedback from the mechanics.

What about kinematic, did Gwin have much to say there?

Yeah, at the beginning, everything was perfect. We tested it on the race tracks and it took us nearly the whole first season to make the final decisions. We made the beginning stroke a bit plusher, to go faster into the sag position; the mid stroke is a bit more responsive so the bike is a bit higher a bit more supportive; and the end progressivity is reduced by 5 per cent.

He told us when he was riding rough stuff, deeper in his travel in some cases, he felt it and there was too much progression. But the basic statement was, it's better to have too much progression because then you can control the bike easier. So we reduced it a little bit and now it feels super smooth but still progressive.

What influenced the decisions on mid stroke support?

Aaron was playing a lot with the length of the cranks. It's like on a snowboard, if you slightly change the angle on a snowboard, you'll have a better feeling. And that's the same theory he was following and checking. If you ride a bit longer cranks, so your feet are a bit more spread on the bike, it could give you a bit more stability but a longer crank, even a few mm, will reduce clearance.

So on some tracks working with longer cranks he asks if it's better to have a slightly higher bb but we don't want to have a higher bb so that's why we changed the kinematic to keep the bike a little higher. That's the miracle! It's interesting, small, minor details to work on but with such a great feedback it makes it worthwhile.

What about 29ers?

Yeah, they are great! We have the Capra 29er which is a super-fast bike. If you compare back-to-back to the Capra 27, it's super interesting. That's why we do not tell the consumer, which size they should go for. If you are faster or not, depends on your riding style and the track.

Lucky me! since Sunday I can tell you this track is not necessarily faster on the 29er because we won with 27 and the other riders had brilliant timings too.

Yes but with 29ers, obviously yes, it is coming, for sure, it has to. But it's a niche, it's really a niche in the niche.