For anyone following the World Cup cross-country racing this year, you will have seen XCO phenom (and 2016 XCM World Champion) Jolanda Neff racing on a new full-suspension bike. There’s nothing totally crazy about that, but until the racing at the UCI XCO World Championships in Canada on the weekend, the shock and linkage on the frame resided under a frame sock of sorts.
With the cover on there, you can pick a few things. Trek still use their Control Freak cable management although only for the brake hose given the AXS wireless setup), there is a main pivot that is quite wide, and there is no drop out pivot.
But with that cover revealed for World Championships, more is revealed. But what is going on exactly?
Seen from behind, we get a few more specifics about the bike. Firstly, the Supercaliber is back – a marquee from the Gary Fisher period.
Also, we can see just how slender the stays are, and like so many top full-suspension XC bikes, the flex in the stays is being used instead of a dropout pivot, saving weight and maintenance and adding lateral stiffness according to engineering boffins.
The rear brake is post mount, not flat mount like the Canyon Lux, and it looks like it might clear a 180mm rotor if you needed one, although this is a 140mm fitted. The main pivot is reasonably high, sitting inline with probably a 34 or 36t chainring. This bike is meant for racing after all. With what looks to be a 2.2″ tyre fitted, there is ample clearance for mud, with no seat stay bridge on the swing arm. The chainstay swing arm wraps around the front of the frame, no doubt help stiffness but also keeping the chainstays as short as possible. It even looks like the brake hose comes out of the back of the bottom bracket shell – but that is a guess.
So what about the shock on the new Trek Supercaliber?
No surprises here, the rear shock is nestled into the top tube, and there is a cable remote at the front of the shock. This is operated by the twist grip lock out along with the RockShox SID fork.
But check out how long the shock body is! With a rear eyelet just in front of the seat tube, and the front well up the top tube, this looks to be really long. Like around 260mm or more. And that long enclosed section of the frame is not pushing one end of the shock, so it must be sliding a sleeve. What exactly is going on here?
Look closer again and you can see a Fox logo on the shock, and there is a new mounting system up front too. It almost looks like a collar that locks the front end of the shock in place. But that certainly looks like a bushing or seal on the front side of the frame covering the shock, and the plug on the underside may be what holds the sliding outer in place? There is clearance for the frame section to move fore and aft, and who knows, maybe there is even a light weight rail system there akin to a Yeti downhill bike from over a decade ago? More likely is that it is keyed, like the Bontrager dropper posts, to keep the action straight. The tolerances between the sliding part and the frame are small, so it must run very true.
Trek have done a lot of work with reducing stiction in suspension systems with their Re:aktiv valving, and this could well be the next step, creating a light weight and stiff cross-country bike with a super supple stroke off the top, perfect for traction over roots and small rocks, keeping the rear wheel stuck to the ground for traction.
The black cover would be for securing the frame to the sliding part of the shock, so it can be removed for servicing. Our best is that the increased shock size is being utilised for a very large negative spring chamber, to keep stiction to a minimum, while also allowing a large positive chamber to allow low operating pressures. But this could all be wrong.
Benefits of the new Trek Supercaliber design
While we can only work on what we can deduce from the photos, there are clearly mounts for a second bottle cage – a huge bonus for those tackling marathons and stage races. The rear shock sits clear and should allow at least a 600mL bottle into the seat tube position – and we assume the main position is a 3-bolt fitting like on many bikes, meaning you can run it further forward when running two bottles, or lower down like Jolanda is when using one bottle.
Given the expected capacity of the rear shock, it should run at very low pressures as well. The Canyon Lux is similar, and it means the suspension can not only be very supple with less initial stiction, but there is less pressure on the seals and internals, which prolongs their life.
Is this only for the XCO crowd, or will it suit marathon and stage races?
With the updated Trek Top Fuel sporting 120mm of front travel and 115mm out the back, stiffer forks, slacker angles and in general a ride that sutis fast trail rides as well as aggressive stage races, the new Supercaliber slides in to fill the pure racing position in the Trek category. Whether it is 50, 60, 80 or even 100mm of travel remains to be seen, but we would expect something pretty short travel to be delivered.
With dual bottle cage options, and undoubtedly a race-ready ride this could well be the ticket for those chasing podium level performances at fast marathons where a hardtail has a little too much sting, or at stage races where the terrain hasn’t been turned up too far.
We hear the release date is imminent, so let’s see what the true story is inside the frame.