2023 Trek

Supercaliber 9.9 XX1 AXS

With razor-sharp handling and ridiculous urgency under power, the new Supercaliber is an incredibly capable cross-country machine in the right hands

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Trek’s new Supercaliber is very much an evolution of the original ‘revolutionary’ design. As a result, it feels like a very sorted, balanced and predictable XC bike, its eagerness for speed clear from the first pedal stroke, and that makes it one of the best XC bikes we’ve tested. And it’s by design. Because apart from a significantly slacker head angle (67.5º down from 69º) the Gen 2 Supercaliber doesn’t look dramatically different to Gen 1.  Frame and geometry Trek even made a conscious decision not to alter the rest of the geometry much (reach and seat angle are slightly increased) so as not to disturb the riding position for their finely tuned pro athletes. Scrape away the multiple paintwork options though (three alone on the flagship SLR 9.9 XX AXS model) and there’s a completely new set of tube profiles. The SLR frame uses a more exotic carbon fibre construct than before and the internal ‘trunking’ for the frame routed brake hose and dropper cable have been removed. Also seeing as Trek’s pro racers generally removed the Knock-Block steering limiter puck from the top tube, that’s no longer fitted either.  Taken together, these updates give an average weight saving of 200g (depending on size) compared to the Gen 1 bikes. Which puts the frame right on the 2kg mark that most serious racers would consider the competitive ceiling. Racers will also be pleased to hear you can fit a 38 tooth chainring and the bike comes with two carbon bottle cages fitted as standard. Trek is still sticking with its extra wide PF92 bottom bracket as it says the stiffness to weight gains from the bigger tube junctions are too good to ignore. The bottom bracket height also raises 10mm to reflect the increased travel and the main pivot position also comes up 10mm in relation to the BB to increase the anti-squat, so the bike pedals better too. Suspension The heart of the Supercaliber’s 80mm rear suspension is Trek’s unique IsoStrut design. This is essentially a small RockShox SIDLuxe based shock hidden inside a 38mm diameter alloy tube (IsoStrut) that bolts into the top tube at both ends. Then the carbon seat stay head forms a larger tube that slides along the IsoStrut on a bushing borrowed from the RockShox ZEB fork; it has 38mm diameter legs.  The slider then connects to the inner shock through a slot to stop it rotating, so the whole unit acts as a structural frame member. Hence the increased stiffness. Despite claims of it being lighter, the IsoStrut element alone without the seat stay head, bushings etc. is over 100g heavier than a standard SIDLuxe shock. Talking to the Trek design team during testing they assured us that achieving similar stiffness from a conventional linkage system like that seen on the 120mm travel Top Fuel, would incur a significant weight penalty.  Thankfully things are a lot simpler up front where the latest RockShox SID SL Ultralight 110mm travel fork is hardwired to …Continue reading »

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The Trek Supercaliber has been completely overhauled for 2024 with two new frames, updated geometry, an increase in travel & a new IsoStrut.

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