Ever since that spy shot that we were able to grab at the 2015 Kenda Cup race in May, the Trek Procaliber SL has been one of the most anticipated bikes of the year. Cross-country purists have been busting out fresh leg razors in eager anticipation of the release of what Trek hopes will be the next standard for hardtail cross-country race bikes. Trek has been using IsoSpeed decouplers on its road bikes for a few years now, and it’s no surprise that Trek has now introduced the technology onto its hardtails. After a quick trip to Holland to see the unveiling of the Procaliber, we knew we had to get one and put it through its paces—and, of course, see what all the fuss is about the IsoSpeed decoupler.
WHO IS IT MADE FOR?
This bike has cross-country racing written all over it and turned the heads of aggressive XC riders on almost every trail that we hit. Most hardtails are built for riders with a specific race plan, and the Procaliber fits right into the mold of those who know exactly what they want. Our test bike is a 17.5- inch frame and is spec’d with 29-inch wheels. Trek created this rig with its Smart Wheel Size concept, which gives the smaller frames 27.5-inch wheels to match the stature of smaller riders.
Even though our test bike is at the top end of the stock build options at $8000, the Procaliber SL starts at $2500 for a frame and has a few price levels in between. Since this bike is available in Project One, the sky is the limit for how much you can spend customizing it.
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Take the fast line: The Procaliber is flat-out fast and wants to be pushed. Through fast turns the tight wheelbase gives the Procaliber an incredibly responsive feel.
Take the fast line: The Procaliber is flat-out fast and wants to be pushed. Through fast turns the tight wheelbase gives the Procaliber an incredibly responsive feel.WHAT IS IT MADE FROM?
Since this will become Trek’s flagship race bike, the frame is woven with lightweight OCLV carbon that works in conjunction with the IsoSpeed decoupler. The IsoSpeed decoupler is what makes this bike so different and special. According to Trek, the IsoSpeed system increases vertical compliance by a staggering 70 percent. Our first impression when we saw the spy shots of the Procaliber was that this would be a hardtail with a little suspension, but after spending time on this bike, it’s clear that the IsoSpeed design is not built around suspension, but instead, around the idea of making the ride more comfortable. There is a difference between comfort and capability, and while the Procaliber is every bit a hardtail, it is a unique and effective approach
to increasing trail comfort.
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The moneymaker: This little piece of technology is what sets the Procaliber aside from the rest of the competition. The ISO Speed decoupler smooths out the ride and makes it a little easier to ride a hardtail in the sense of comfort.
The moneymaker: This little piece of technology is what sets the Procaliber aside from the rest of the competition. The ISO Speed decoupler smooths out the ride and makes it a little easier to ride a hardtail in the sense of comfort.Speed and performance were put at the forefront when designing the Procaliber. Modern geometry, Boost 148 hub spacing and internal cable routing give this Trek a sleek look, and the bike is flat-out fast. We have reservations about the practicality of internal cable routing from a maintenance standpoint, but Trek uses its new Control Freak system to make routing easier and to allow the frame to work with mechanical or Di2 electronic drivetrains on the same platform.
WHICH COMPONENTS STAND OUT?
With as flashy a build kit as the 9.9 offers, it’s tough to pick just a few components that really stand out. The Bontrager XXX Lite bars and stem are stiff and light, while the RockShox RS-1 is one of the stiffest forks that we have ridden. This was the third set of DT Swiss XMC1200 wheels that we have tested, and so far we’ve been impressed with their overall performance. The Race Face Next SL cranks add to the bling factor, making the Procaliber pure eye candy for the cross-country faithful.
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Balance of weight and stiffness: The Procaliber frame is incredibly light, while the RS-1 fork is incredibly stiff. Trek believes that this combination is the best recipe for winning.
Balance of weight and stiffness: The Procaliber frame is incredibly light, while the RS-1 fork is incredibly stiff. Trek believes that this combination is the best recipe for winning.![Procaliber10]()
Pull out all the stops: Between the carbon DT Swiss XMC1200 wheels, XTR components and slick frame, the Procaliber turns heads. The lines of the frame are modern and look fast, especially with the internal cable routing.
Pull out all the stops: Between the carbon DT Swiss XMC1200 wheels, XTR components and slick frame, the Procaliber turns heads. The lines of the frame are modern and look fast, especially with the internal cable routing.
Eye-catching details: To keep the weight down, Trek spec’d the Procaliber with the Race Face Next SL cranks, which are some of the lightest available. The combination of weight and stiffness made for an efficient ride.
HOW DOES IT PERFORM?
While the IsoSpeed decoupler is a complex piece of engineering, the overall performance concept is pretty simple. Out of the saddle the Procaliber rides like a true hardtail; in the saddle the bike feels like it’s floating over imperfections on the trail—deep ruts feel a little shallower, rocks feel a little smaller, and the trail a little smoother (due in part to the 29-inch wheels). On long fire roads the Procaliber felt unbelievably smooth, and we really understood Trek’s success on the road with the IsoSpeed design.
Moving out: Right away we could feel the comfort of the G2 geometry. Our test rider was 5-foot-9, though, and the 17.5-inch frame did feel a little small to him at times. Riders who are on the fence with sizes should really look into the numbers and fit before making a purchase. The stem and bar combo, in relation to the reach and drop, did allow for more precise handling.
Cornering: The Procaliber has a very tight wheelbase, which made the bike feel incredibly nimble and surprisingly easy to push through corners. After we swapped tires to a wider set of 2.1s, we noticed a drastic difference in the cornering of the bike. The low- rise, wide bars put us in a good position and made the bike feel balanced on everything from flowing singletrack to steep and fast pitches.
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Up and away: Between the 29-inch wheels and incredibly light frame, this bike will climb for days. The torsional stiffness of the RS-1 fork is an added bonus to how well the Procaliber will handle any mountain.
Up and away: Between the 29-inch wheels and incredibly light frame, this bike will climb for days. The torsional stiffness of the RS-1 fork is an added bonus to how well the Procaliber will handle any mountain.Climbing: It climbs like a race bike; there is do doubt about that. On almost every climb we found ourselves sliding forward on the saddle, putting our heads down and hoping for a KOM. When locked out, the RS-1 was stiff and responsive when we pedaled hard out of the saddle. On long days we felt the benefits of the IsoSpeed frame and had less soreness the day after. We did notice that the rear triangle would give a little when we would work hard out of the saddle. The seatstays are relatively thin, which makes them more compliant, but they did seem to flex some when we pedaled hard out of the saddle.
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It does a lot: While the Procaliber is built to be a hardtail race bike, it doesn’t shy away from a drop or jump. The compact geometry makes the bike incredibly nimble and fun to ride.
It does a lot: While the Procaliber is built to be a hardtail race bike, it doesn’t shy away from a drop or jump. The compact geometry makes the bike incredibly nimble and fun to ride.Descending: For a cross-country hardtail, the Procaliber truly is a fast and playful bike. We noticed how easily it would accelerate and how effortlessly it carried its momentum down the trail. In flat sections that normally required more pedaling, the Procaliber ate up the trail and carried speed with ease. The RS-1 isn’t the lightest cross-country fork out there, and it did weigh down the front end some, but it made up for that by giving us extra stiffness and stability. We felt the benefits of the tight wheelbase, as the bike felt very balanced at high speeds and in steep sections.
TRICKS, TIPS & UPGRADES
We didn’t have many complaints about the build kit, and have really struggled to determine which parts to swap or upgrade. If anything, the Bontrager XR1 Team Issue 29×2.0 tires were fast and offered little resistance, but we did swap to a pair of WTB Nano 29×2.1s, and with the slightly wider tire we noticed a big difference in capability on the descents. We didn’t lose too much, if anything, on the climbs.
One of the issues with 1x drivetrains is trying to find a front chainring that will suit a majority of riders. The Procaliber 9.9 comes with a 32-tooth front ring, which we think made this bike very under-geared. We spun out pretty easily on flat and downhill sections. Some of you might not think you’ll be able to push a bigger ring, but if there’s any bike that will allow you to run a bigger gear, it’s this one.
BUYING ADVICE
A hardtail at this level has a very focused demographic, especially given the price. If your local trails are smooth and flowy cross-country havens, the Procaliber will give you all the efficiency and fun that you need. If you’re an aspiring racer, the Procaliber is a fast machine that will allow you to push yourself but keep you comfortable while reaching for the top step. Either way the Procaliber could be a dream bike that is worth the coin and delivers on the promise of speed and comfort.
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