On Test | The 2021 Trek Supercaliber 9.9 – Project One Style


Designed to excel at the very pointiest end of the sport, the Trek Supercaliber is a premium, 100% unfiltered, unapologetic, pure-bred XC race machine. The Supercaliber was first announced to the world last year, stunning many with its striking carbon chassis, integrated IsoStrut suspension design and impossibly thin seatstays. In a market where many full suspension designs are beginning to look much the same, the Supercaliber, with its near hardtail-like profile, proved that Trek is still willing to invest and innovate in this arena. Looks are one thing though. To see how this distinctive race bike compares to the likes of the Specialized Epic, Cannondale Scalpel and Orbea Oiz on the trail, Trek has sent us a very special Supercaliber to put to the test.

2021 trek supercaliber 9.9 xx1 axs project one
Replacing last year’s Top Fuel, the Trek Supercaliber is high-octane full suspension XC race bike.

The Trek Supercaliber – Give Us The Lowdown

For all the nitty-gritty details about the new Trek Supercaliber, make sure you check out our feature article here. In a nutshell though, the Supercaliber is a full suspension XC race bike that’s designed around 29in wheels and a 100mm travel fork. The frame is made from Trek’s OCLV Mountain carbon fibre, which is used on every Supercaliber model, regardless of price point.

2021 trek supercaliber 9.9 xx1 axs project one
Thanks to the low-profile IsoStrut suspension design, the Supercaliber will happily accommodate two water bottles inside the mainframe.

The IsoStrut design is unique to Trek, and offers up 60mm of rear suspension travel via a hidden Fox Float DPS shock and carbon fibre flex stays.

The rear suspension is where things get really interesting though. Using what Trek refers to as IsoStrut, the rear shock is partially integrated into the top tube, where it’s driven by a carbon fibre carriage that slides up and down a big alloy stanchion. That carbon fibre carriage is moulded directly into the swingarm of the frame, essentially creating a very simple two-piece suspension design that is devoid of any separate linkages. There are no pivots around the rear axle, instead the thin seatstays are designed to flex and bow as the shock is compressed.

2021 trek supercaliber 9.9 xx1 axs
The IsoStrut design comprises of a carbon fibre carriage that slides up and down a single alloy stanchion tube, compressing a Fox shock hidden within.

The Supercaliber differs from many of its competitors in that it produces just 60mm of rear travel. For XC racers who are regularly debating between choosing a hardtail and a full suspension bike, the Supercaliber could strike the ultimate balance between both. Furthermore, space-efficient IsoStrut suspension design means there’s clearance to run two water bottles inside the mainframe, which is becoming an increasingly expected feature on XC and marathon bikes.

What The Heck Is ‘Project One’?

Ah yes, the mysterious-sounding Project One! This is Trek’s custom bike builder program, which gives you access to several key models in the road and mountain bike lineup, and allows you to customise things like the paint job, graphics, groupset, wheels, tyres, saddle and cockpit.

The Supercaliber is one of the models available in the Project One bike builder, and the bike we have here is based around the stock Supercaliber 9.9 XX1 AXS model. In fact, it’s virtually identical in terms of the build, but it’s treated to a very special paint job that Trek calls ‘Holographic Diamond Flake’. It’s got a lovely glossy black finish with speckled diamond flakes throughout, giving it a sort of exotic-dinosaur-egg-from-outer-space vibe. If you know what we mean.

2021 trek supercaliber 9.9 xx1 axs project one
Trek’s Project One program allows you to go for a very snazzy paint job like this one.

This particular option is one of the six ICON paint jobs, which you can choose from in the Project One bike builder. Anyone can jump on there and build their own custom bike, but we must warn you, be prepared to spend a lot of time on there! If you decide to go ahead with your masterpiece, you can forward your order onto your local Trek dealer. The bike is assembled in the US at Trek’s Wisconsin headquarters, and then the bike is airfreighted to your dealer, usually within a few weeks. It’s actually a relatively quick way to get a new bike – in fact, that’s why we have a P1 bike on test, because it was quicker to go custom and have it airfreighted, than wait for a regular stock model to arrive by sea freight in Australia.

2021 trek supercaliber 9.9 xx1 axs project one
There are six ICON paint jobs available, including the Hollowgraphic Diamond Flake shown here. Or you can choose a zillion other paint combos in the Project One bike builder. Just get ready to waste A LOT of time doing it!

Are There Standard Models Too?

There certainly are – it’s your choice if you want to go for a stock model or the Project One route. There are five models available in the 2021 Trek Supercaliber range, with prices starting at $8,699 AUD for the Supercaliber 9.8 GX model. If you wanted to go fully custom, there’s also a frameset available for the very specific amount of $4,676.04 AUD.

As mentioned above, our test bike is based upon the very top-end Supercaliber 9.9 XX1 AXS model, which normally sells for $15,599 AUD. So the Project One element does add to the price, in our case an extra $750 AUD. We reckon that’s pretty good given the customisation available.

Read on for a closer look at the specs of our newest test bike, and stay tuned for an in-depth review to see how the Supercaliber stacks up against the competition.

2021 trek supercaliber 9.9 xx1 axs project one
Our test bike is based upon the stock Supercaliber 9.9 XX1 AXS model, complete with a RockShox SID SL Ultimate fork and Bontrager Kovee XXX wheels.

2021 Trek Supercaliber 9.9 XX1 AXS Specs

2021 trek supercaliber 9.9 xx1 axs project one
The lightweight cockpit features 720mm wide Bontrager Kovee XXX carbon handlebars, and the Knock Block steering limiter.
2021 trek supercaliber 9.9 xx1 axs project one
There’s a 100mm travel RockShox SID SL Ultimate fork up front, though Trek says the Supercaliber frame will take up to a 120mm travel fork. Perhaps we should try that?
2021 trek supercaliber 9.9 xx1 axs project one
Stay tuned for our in-depth review on Trek’s go-fast race bike.

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