TREK SUPERCALIBER 9.7:

The New XC Race Benchmark + Factor O2 Disc, Specialized Epic Expert Carbon

TThe Trek Supercaliber was the worstkept secret in mountain biking in 2019.

It was rumoured, spy-shot, and raced throughout the UCI Mountain Bike World Cup by high-profile Trek pro riders →olanda Neff and ▲llen Noble, top-secret rear suspension shielded by a fabric sleeve. That Trek designed a custom sleeve just to disguise the Supercaliber’s rear end tells you something about the black magic at the back.

Now the secret’s out, and its name is IsoStrut. The Supercaliber is an unapologetic, uncompromising XC-race machine, and IsoStrut is what separates it from any other bike you can buy today.

The structurally integrated system uses a main pivot and a customdesigned ▶ox shock that lives within a Kashima-coated strut. There’s no pivot at the rear axle; the thin seat stays are designed to flex. The shock provides about 55mm of rear travel, with the flexing stays adding 3 to 5mm of deflection, for a total rear travel figure of 60mm.

Indeed, the Supercaliber aims to bridge the gap between a fastpedalling hardtail and a more capable full-suspension race rig. On XC-oriented singletrack, with rocks and roots but no obstacles larger than you’d find on a World Cup course, the ride is sublime. It pedals extremely well: there’s almost no bob under hard acceleration, yet the suspension becomes active over rock gardens and descents.

The Supercaliber was in development for three years as Trek grappled with the essential XC race-day question: do you spring for an efficient-pedalling hardtail, or a fast-descending fullsuspension model? Prior to this season, Trek pro riders could pick the

Procaliber – a 100mm hardtail with a rear de-coupler that provides 11mm of undamped travel – or the 120/115mm Top ▶uel, a full-suspension bike that’s become slacker and less race-focused over its lifespan.

The company observed that its racers tended to pick the Procaliber if they thought they could get away with riding a hardtail, reserving the Top ▶uel for the most challenging courses. That defines the rationale for the Supercaliber: a short-travel full-suspension rig with the lightness and responsiveness of a hardtail.

The ground-up race focus is apparent. The size-medium frame weighs 1 933g – amazingly, 23g less than a medium Procaliber. This is made possible by eliminating the swing link and second pivot at the rear axle, and instead using thin, lowmodulus carbon-fibre seat stays to handle the IsoStrut’s travel. Trek uses three sizes of rear triangle to tune the frame for different rider sizes, thereby maintaining low standover heights across the size range.

The 9.7 featured here is the base Supercaliber. You get the same OCLV carbon frame, IsoStrut, Boost 148mm spacing and internal routing as on the rest of the line. Cost saving comes in the form of the components and front fork: SRAM NX ▲agle 1x12 drivetrain and a RockShox Reba RL. The rims are carbon – Bontrager Kovee ▲lite 23s – which helps to keep the overall weight of a medium bike to 11.24kg. (The top-spec Supercaliber 9.9 AXS, which costs an eye-watering R175k, weighs in at an incredible 9.4kg.)

Ride enough trail bikes with long, low, slack geometry, and you might forget what it’s like to really control a bike. The Supercaliber reminds you very quickly: on more technical, definitely-not-XC terrain, it’s a bike you have to ride deliberately. There’s no slack head-tube angle, dropper post, or long-travel fork to save you if you get your line wrong. You can certainly find a rhythm on technical, root-filled trails, you just have to be a better bike handler than I am.

But in its element, the Supercaliber is superb. You get razor-sharp acceleration; the steering feels sharp; and – as a 29er – the bike maintains momentum with ease. It’s simply everything you want from an XC race bike. If someone riding a Supercaliber beats you next season, take solace in the fact that their bike is faster than yours. – Dan Roe