What’s the fastest mountain bike for the Leadville 100? Until recently, most would argue a hardtail – nice and light for the climbs – or even a full-suspension bike to soak up the bumpy descents and vibrations. The race has been won on both numerous times. But both would of course have flat handlebars.
Dylan Johnson is known for his unconventional tech choices, something he is transparent about on social media and in YouTube videos. He likes to geek out on training methods and aero hacks that he feels give him marginal advantages. Marginal gains philosophies have slowly been making their way into mountain bike racing (Pauline Ferrand-Prèvot won the Olympics with aero shoe covers, for example) but Johnson is one of the few willing to completely rip up the normal playbooks.
Last year at Leadville, he was aboard a drop bar-equipped hardtail mountain bike. This year, he’s upped the ante and gone full suspension with curly bars.
Johnson is sponsored by Felt and finished in a career-best 10th place at Unbound Gravel this summer aboard a Breed gravel bike with 2.2-in mountain bike tires on 60 mm-deep Reynolds wheels, a 35 cm handlebar and a Lauf suspension fork, but the manufacturer no longer makes mountain bikes. That freed him up to make his own choice, securing a BC-40 frame from Arkansas-based brand Allied Cycle Works.
“I did some calculations on Best Bike Split,” Johnson told Escape Collective in the backyard of his Leadville rental house. “So assuming there’s a two-pound weight difference between full suspension and a hardtail, which is a safe assumption for most brands – sometimes it’s a little bit more – the weight penalty would be a two-and-a-half-minute difference for the entire Leadville course. And I personally thought that I could make up two and a half minutes by having rear suspension, so I went with it.”
Johnson is betting the ground-hugging efficiency of a full-suspension setup will also help him reduce fatigue over the course of 100 mountainous miles.
Also relevant to the weight conversation on mountain bikes are dropper seatposts. Many will opt for a rigid post, but Johnson went with a Fox Transfer dropper, which he says is only 250 grams heavier than a rigid post. Not one to shy away from math, Johnson calculated that the ability to drop his seatpost on the descents will save him 40 seconds across all the descents on the course.
Then there is the marquee component of the bike: the drop bars.
“My calculations put the drop bars six minutes ahead of flat bars for the entire course,” Johnson says. “And when doing those calculations, I took out any sections where you could use the puppy paws position [on flat bars], because then it kind of doesn’t matter what bar you have. And I assumed slower downhill times, which, at least for me at this point – given how much I’ve been riding this bike – is not necessarily the case. Some of my downhill times have been right on par with my flat-bar times.”
Accenting the frame is a new Fox 32 Step-Cast fork with the Grip SL damper, 200g lighter than the older model, according to Johnson. He is not running a remote lockout, partially because it’s hard to rig to the drop bars and partially because he wants the aero saving of not having as many cables up front.
The bike is powered by a SRAM XX1 Eagle drivetrain, notably not the newer SRAM Transmission. That’s because Johnson wanted to run a KMC chain, which he says is slightly more efficient than a SRAM chain.
Up front is a 36-tooth chainring. He didn’t want anything bigger because he wants to be able to stay in the middle of the cassette for longer when climbing. You guessed it: it’s more efficient that way.
Finally, the bike rolls on 2.35-in Schwalbe Thunder Burt tires mounted around Reynolds wheels.
“The Schwalbe Thunder Burts don’t handle well,” Johnson said. “They’re extremely sketchy, but it was a risk I’m willing to take considering that this is probably the fastest tire that you can buy. I am not sponsored by them so that’s coming straight from heart when I say that.”
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