Trail Testing: Cannondale FSI Carbon 2

Hardtails are quickly becoming more and more advanced machines, capable of not only flying up technical climbs but descending like a full-suspension trail bike.  The Cannonade FSI Carbon 2 is a perfect example of a cross-country race bike that rips down hill just as fast at it goes up.  With a handful of rides under our belts thus far, we have quickly learned that the FSI is all business.

It was easy to see that Cannondale took their time with the FSI. Everything is built around efficiency and not accepting any compromise on the trail. The slacked out head angle and 55 millimeter offset on the 100mm travel Lefty PBR offer a lot of confidence while descending, while the light, stiff Hi-Mod frame allow for more efficient climbing.

The Carbon 2 has an X01 build kit with a 32t ring up front. Cannondale uses a couple of their in house accessories for the build such as a carbon flat bar, carbon SAVE seatpost, Fabric saddle, and of course Si cranks. Up front doing the stopping is a set of Magura MT6 brakes. With Stan’s rims wrapped in Schwalbe Racing Ralph 29×2.1 tires, this build is ready for any cross-country race.

So far we have enjoyed some long days in the saddle and are anxious to see how much the FSI can handle.


    Our Ai design shifts the drivetrain and rear triangle to the right by 6mm. This creates an ultra stiff rear wheel by reducing dish, and delivers the shortest chainstays on the market, dual chainring compatibility, tons of mud clearance, and a super responsive rear end.
    By keeping the rim and tire in line with the centerline of the bike, but shifting the hub and cogs 6mm to the right, we make the spoke angles more even on both sides, creating a stronger wheel that’s up to 60% stiffer than a conventionally laced wheel, while using a standard rim and normal 135mm hub.
    The Ai system allows for the shortest chainstays on the market (429mm), which moves the rear wheel forward to be more under the rider, resulting in exceptional lateral stifness and racewinning traction.
    The F-Si spider moves the chainrings out 6mm to match the rear triangle with no change in Q-factor. This enables the super short chainstays while providing ample mud clearance for the tire and maintaining double and single ring compatibility.
    Up front, the progressively slack 69.5° head angle gives the stability needed to attack on rough, fast descents, while the Lefty’s proprietary 29’er-specific 55mm fork offset reduces “trail” keeping the steering quick and nimble in slower, tight, technical sections. In back, the super short chainstays make the bike extremely agile for technical manuverability and crazy traction.
    By pairing precise tube shapes with sophisticated carbon lay up, we are able to create areas on the rear chainstays and seat stays and seatpost that can deflect to absorb shock, while staying completely rigid laterally and torsionally. This enhanced vertical compliance greatly improves rider comfort and rear wheel traction, so you can ride faster, longer.
    The all-new SAVE seatpost has been redesigned to save almost 50 grams and deliver 20% more deflection. It has a more linear deflection curve, which means more comfort, especially for lighter riders, while maintaining strength for max loads.
    Our proprietary carbon construction method pairs ultra strong military armoring fibers with high strength resins and a tightly controlled network of high-modulus stiffening fibers to deliver ultra light frames with exceptional strength and ride-feel. Oh yeah, and lifetime warranties.

The wrecking crew strives to put as many miles on each test bike before we write a full review. Watch for the full write-up on this bike in the coming pages of Mountain Bike Action.


29er race bikecannondalecannondale fsicarbon hardtailhardtailmountain bike action trail testing