If you’re looking for a rapid handling cross-country hardtail then the X-Caliber delivers in spades, but it’s a bit of a handful when the trail turns downhill thanks to steep geometry and a dated cockpit.

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The X-Caliber range is Trek’s entry to their proper cross-country hardtail offerings, designed to tackle proper off-road riding rather than being a multi-sport machine. All share the same aluminium frame and that’s a very good thing as it’s really well made for the money, with a lot of thought having been put into the double butted, mechanically formed tubing.

At the rear, the wishbone seat stays aren’t braced before they attach to the seat tube, giving masses of mud clearance and also allowing a touch more compliance in the back end. Along with a slender 27.2mm seat post, that means the X-Caliber is no harsh, back-jarring machine over the bumps and with an integrated headset, it’s a tidy looking frame too.

Size specific wheels

A really neat feature of the X-Caliber range is while there are seven different frame sizes on offer, the smallest two bike frames using 27.5” wheels rather than the big 29” hoops that the rest of the range uses. That means that handling should be balanced to suit rider height, with frame angles tweaked to suit as well. The big wheeled bikes also use a special Trek-developed fork offset designed to work better with the 29” wheel size.

The X-Caliber 9 is the most expensive bike in the range and gets a very respectable kit list for the money, though as Trek still sell bikes through traditional bike shops it can’t quite touch the value for money that direct-sales brands offer. That said, it does mean you’ll be able to get face to face advice and try before you buy, which can be worth a lot more than a few extra trinkets on the bike.

Up front there’s a RockShox Rekon Silver RL offering 100mm of travel, or 80mm on the smallest frame size bikes. It’s air sprung, so it’s a simple task to get it set correctly for your body weight and you get adjustable rebound damping along with a lockout that’ll stop everything bouncing up and down on smooth sections. It’s a surprisingly well controlled fork off road, with the damper doing a sterling job of keeping control despite the relatively short overall travel. It still uses normal open dropouts rather than a stiffer, more secure through axle design. Along with the relatively long and skinny legs, that does mean there’s some flex in the fork and steering precision isn’t great once the going gets seriously tasty.

Dated cockpit and angles

More importantly, the X-Caliber’s dynamic ability is let down by geometry and a cockpit that has its basis in very traditional views of how a cross-country machine should handle. The 69.6º head angle is pretty steep and certainly means the bike is very responsive to your input, but along with the long 110mm stem it rapidly becomes a twitchy handful for all but the most quick witted of riders when you choose to point it downhill on all but the mildest of gradients. While the respectably long reach means you should have plenty of space to move your body about and maintain a stable position on descents, that big stem forces your body weight so far forwards that technical trails have you worrying about going over the bars or letting the front wheel tuck under on tight, steep corners. If you’re a head down, pedal and suffer racer than might be acceptable, but for the less experienced or more aggressively minded rider it’s an unrewarding experience.

Trek-X-Caliber-9-2017-108.jpg, by Russell Burton

That’s a real shame as the rest of the bike works cohesively, with the twin ring drivetrain, ten speed drivetrain snicking smoothly across gears, even under power. Ideally, there would be a clutch equipped mech to prevent chain derailment, but as long as you keep the pedal to the metal it works very effectively under power and the Shimano Deore shifters shift with a smoothness that’s barely imperceptible from their much higher end offerings, albeit at a mild weight penalty. Shimano also provide great stopping power in the form of the M365 hydraulic brakes. Yes, the lever is quite long and clunky compared to more fancy items in Shimano’s repertoire but they do the job of hauling you up in all conditions with aplomb, even with dinky 160mm rotors. At 13.2kg for the 19.5″ frame it’s a decent weight too.

Wheely good wheelset

Apart from the great big stem, Trek’s house brand Bontrager has provided some excellent finishing kit, with special mention going to the wheelset. Despite the low spoke count, it’s stiff and accurate, offering an easy upgrade in the form of tubeless ready rims. Talking of upgrades, if you ride anywhere with mud, you’ll be wanting to see the back of the skinny Bontrager XR2 rubber sharpish. It’s mega fast rolling thanks to low profile tread but the lack of width means you need to overpressure it to prevent pinch punctures, with a resulting lack of comfort despite the fact the big hoops help smooth out trail chatter. That low profile tread verges on the lethal when the going gets sloppy too. 

All in all, the X-Caliber 9 has a lot of potential. If you’re willing to make it – and yourself – work very hard, then it’ll reward with a responsive, sharp and precise ride character that won’t beat you up like cheap aluminium frames often can. On flat, flowing singletrack, it’s precise and lively, while covering ground will come with ease. It’s a real shame as it could do all this and much more if Trek had calmed down those race roots, relaxed the geometry and butched up the cockpit. With a mild tweak, this could be a seriously rapid hardtail; not just up up and along, but also down. 

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