Few people would be surprised to hear that downhill bikes have been the last holdout on making the switch to 27.5in wheels but now that the shift is in progress, it's happening at a feverish pace. British GT Factory Racing phenom Rachel Atherton is yet another top-name star to make the move, and she used it to good effect in Windham, New York.
Rachel Atherton has made the move to 27.5in wheels this season
Atherton's new GT Fury World Cup strikes a nearly identical profile to the 26in-wheeled one that debuted just last year and from a distance, you'd be forgiven for thinking that it was actually the same bike – and aside from a few geometry changes required to accommodate the bigger hoops, it mostly is.
The Fury World Cup uses GT's long-running Independent Drivetrain (formerly known as i-Drive) system, which offers the square-edged bump performance of a high single pivot suspension design but without the detrimental pedal-induced movement and kickback that normally come with it. Geometry is thoroughly modern, too, with a low, slack, and long setup that's tailor made for modern World Cup tracks.
GT's Independent Drivetrain design offers the bump-eating performance of a high single-pivot wheel path but without the drawbacks
Some might question why someone with Atherton's pedigree is on an alloy chassis instead of carbon one, particularly since GT's previous downhill flagship was just that. However, this new version is supposedly lighter and more rigid than the old composite structure. More importantly, welded metal construction enables GT to more quickly make changes based on rider (or market) demands – both of which are evolving with incredible pace. Given that the 26in version of this bike was only introduced last year, we probably wouldn't have seen Atherton on a new 27.5in version so soon afterward otherwise.
GT claims the current Fury World Cup's alloy frame is both lighter and stiffer than the previous carbon one - and it's far easier to make changes, too
Materials debate aside, Atherton likely cares much more about how her bike is tailored for her build and riding style – and between team mechanic Joe Krejbich and factory suspension support from Fox, it's quite an impressive job.
Both ends are astoundingly supple to the point where even with a modest total weight of "around 36lb [16.3kg]", there's so little seal friction that the bike actually sags slightly under its own mass. According to Krejbich, Atherton nevertheless still prefers the front end to be a little firmer and more supportive to prevent dive under braking and in hard corners.
Both the fork and rear shock are fully custom tuned by Fox
Krejbich says Atherton also likes her Shimano Saint brake levers to have as little throw as possible, and they're positioned quite close to the bars. We also noted how the pins on Atherton's Crankbrothers Mallet DH pedals barely extend out of the platforms. Krejbich says it's because she likes to move her feet around a lot during a run.
Speaking of runs, the GT Factory Racing team on the whole takes equipment setup quite seriously – and the method by which changes are recorded, which unfortunately we can't show you, is perhaps the coolest thing about Atherton's bike. Each and every run done during a race, practice, or test session is logged in details on a custom Apple iPad app so that the team (and the riders) can keep track of how each change affects how the bike performs and feels on the track.
This is as much of the GT Factory Racing team's custom equipment setup app as we're allowed to show you
This meticulous and systematic approach helps the team and riders draw firm conclusions on what works and what doesn't, and also takes out much of the guesswork when it comes to recalling an old setup that felt just right (and why).
Atherton wasn't quite able to make it four in a row in Windham, though, with Lapierre's Emmeline Ragot beating her out by 2.89 seconds for the win. Rest assured, however, that Atherton will be once again gunning for the top step on the podium at the next stop in Méribel, France – and that her team will have a good idea on how to set her bike up to get there.
Complete bike specifications
- Frame: GT Fury World Cup
- Rear shock: Fox RAD, factory tune
- Fork: Fox 40 Float RC2, factory tune
- Headset: Hope Integral
- Stem: PRO The Athertons Star Series Direct Mount, 45mm
- Handlebar: PRO The Athertons Star Series, 760mm
- Grips: PRO The Athertons Star Series
- Front brake: Shimano Saint BR-M820 w/ 203mm RT98 rotor
- Rear brake: Shimano Saint BR-M820 w/ 203mm RT98 rotor
- Brake levers: Shimano Saint BL-M820
- Chain guide: Shimano Saint SMCD-50
- Rear derailleur: Shimano Saint RD-M820
- Shift levers: Shimano Saint SL-M820
- Cassette: Shimano Saint CS-M980, 11-13-15-17-19-21T
- Chain: Shimano Saint CH-M981
- Crankset: Shimano Saint FD-M820, 165mm, 38T
- Bottom bracket: Shimano SM-BB80
- Pedals: Crankbrothers Mallet DH Race
- Rims: Stan's NoTubes Flow EX, 32h
- Hubs: Shimano Saint HB-M820 and FH-M825, 32h
- Spokes: stainless steel, butted, 2x lacing, w/ alloy nipples
- Front tire: Continental DerKaiser Project, 27.5 x 2.4in, tubeless, 25psi
- Rear tire: Continental DerKaiser Project, 27.5 x 2.4in, tubeless, 25psi
- Saddle: PRO The Athertons Star Series
- Seatpost: PRO The Athertons Star Series DH
- Other accessories: Hope seatpost collar