The Jekyll is promoted as a complete, integrated, race-winning system.

It is primarily aimed at the ever-trending enduro racing format but has also topped the podium in the DH discipline as well. Cannondale created the Jekyll to have a two faced disposition, claiming it can effectively perform like two entirely different machines. They accomplish this with a burly frame sculpted to maximize the potential of some proprietary squishy bits in the front and the rear. Out front, there is the startlingly unique Lefty Supermax fork—if you can call it a fork. In the back lives the Dyad damper, an innovative piece of equipment developed in conjunction with the gurus at Fox Racing. The features of each suspension component are intended to work together in altering the riding characteristics of the Jekyll such that, at the flip of a few switches, it goes from being an efficient and responsive short travel pedaler to a chunder-eating speed monster.

Beyond the weirdness accompanying the proprietary stuff, the Jekyll features all the things we are supposed to expect from a modern super bike; wide range 1x drive train, 27.5" wheels, slack head angle, low bottom bracket, a dropper post, and wide bars mounted to a short stem in front of a roomy cockpit. Yet Cannondale has not rested content in simply checking off the proper boxes. The Jekyll represents a commingling of well-selected elements in an integrated design, aimed at a specific purpose and done with attention to detail.

The Numbers

67° head angle
73° seat tube angle (static)
14.3" BB height (static)
24.4" top tube (horizontal, size large)
Stand over hovers around 30". Small: 30.2" - Large: 30.6"
47.6" wheel base (Size large)
30.3" front center
17.3" chain stay
Weight: 27 (ish) pounds
160mm front travel v 95 or 160mm rear travel

The Dyad

It works like two shocks in one, giving both 95mm and 160mm of travel. It is a pull shock so it works in reverse from what most of us are used to. As the suspension goes through its travel the Dyad extends instead of compressing. It employs one negative and two positive air chambers as well as dampening circuits for both compression and rebound dedicated to each travel mode. The positive air chambers combine in flow mode to create a larger volume chamber with a more linear spring rate closer to that of a coil. The dampening has been optimized for 30% sag so more of the stroke is useful compared to previous configurations of the Dyad shock. There is a handy setup guide printed on the seat tube and sag indicators in two locations to assist in setting up the suspension. Switching between the travel modes is done with a handlebar-mounted control. On this test bike, a Sram grip shifter was retrofitted in place of the original lever to actuate control with great success.

The Lefty

It works by using an inverted, dual crown design with hexagonal stanchions above the main seal. Inside, the flat faces of the stanchion slide on floating sets of roller bearings. This is how the single strut can be made torsionally stiff. An added perk is that the roller bearings virtually eliminate static friction, making the Lefty very responsive to small stuff in the beginning stroke. The adjustments available on the Lefty are air spring pressure, rebound, and an open or closed compression setting. Any additional tuning beyond spring rate and rebound require a breakdown to install internal volume spacers. The front wheel employs a tapered axle and hub combo, which is kept in place from the right side by a lock ring installed with a cassette lock ring tool. A (proprietary) keyed brake mount allows the brake caliper to be removed and accurately reinstalled so that the wheel can be taken off sideways if necessary. I.e. You must remove brake caliper to remove wheel.

How it Appears

Evidence of winning intentions litters the frame. On the macro, the finish of the carbon is excellent with clean routing for all control lines (including stealth routing for the seat post). Cannondale employs a military grade carbon branded as "Ballistec" which is supposed to be lighter than alloy and stronger than steel. In addition to the high-grade carbon, special attention was given to protecting the vulnerable parts of the frame from damage and cable rub. There is a rubber bumper protecting the frame against strikes from the fork, a bolted-on down tube shield guarding the bottom bracket area, a shield in front of the Lefty's exposed inverted stanchion, and armor on the chain stay to protect against chain slap. Slightly more obscured are the 15mm thru axles at all suspension pivots and the massive profiles of the tubes, which are at their most substantial in the same critical areas.

Combined, these features create an extremely torsionally rigid linkage between the front and rear triangles. Another small detail is the very useful set up guide for the Dyad shock printed directly on the seat tube. Furthermore, the controls of the selected components are kept few and simple with a single shift pod on the right and controls for the Dyad and dropper on the left. On the test bike, the control for the Dyad rear shock was routed into a Sram two-position grip shifter. This goes a long way towards making the technologies featured on the bike useable.

The Ride

All of the weirdness of the Jekyll melts away into a unique experience on the trail. When actually riding the Jekyll, the fact that half the fork is missing and the rear shock is working in reverse become irrelevant. Everything works as assured and riding the Jekyll certainly brings smiles. This said, there were a number of times I felt overwhelmed and distracted thinking about how it was all supposed to be working. Learning to switch between settings proved useful and was not a total chore, but such a tech-heavy approach to going up and down might require a level of focus that isn't likely on most of my outings. Perhaps in a race mindset there is more willingness to fiddle with settings on the trail.

On the climbing side of things the Jekyll is roomy and efficient. Hints that the Jekyll's focus might be more on descending begin to show as it excels on logging roads but takes some effort and attention on tighter obstacle-strewn trail. Getting the front end up to surmount large roots and ledges benefits from anticipation and preparedness. Yet, switch backs and tight corners on the Jekyll feel stable and predictable both up and down.

The Dyad shock does exactly what it is supposed to do and switches on the fly. In the short travel mode, pedaling efficiency appears from nowhere and the back end remains actively supple over the small stuff. Staying seated is not only possible, but also advantageous while climbing all but the steepest sections. When standing up for some extra oomph, maintaining weight fore and aft is intuitive and the back end maintains traction accordingly. Up front, running the lefty in its "lockout" setting provides enough small bump compliance to assist in maintaining forward momentum and a bob free experience when pedaling out of the saddle.

The Jekyll presents a bit of a compromise when traveling over intermittent sections of trial. The flow mode doesn't like to pedal and the elevate mode doesn't like to flow. However, switching back and forth between the two is easy, instant and becomes reflexive. While the Dyad rear shock excels at these quick transfers, the Lefty struggles because it is not as simple to change settings up front simultaneously. Leaving the fork wide open was the best thing to do in most situations. However I found that getting it dialed in for such duties was virtually impossible with the external adjustments available. In order to get the premium situation, internal volume spacers are a must. Short of this the Lefty offers only air spring rate, opened/closed dampening options, and rebound. As this was a weeklong test period, I did not have the chance to fine tune the ramp up with internal spacers, but I think that if I had the opportunity to customize this aspect of the Lefty it would have gone from satisfactory to amazing.

The trouble I ran into was that when running air pressures low enough to optimize the small bump action in its firmer mode the fork would dive a bit in open mode. The opposite was true when running higher pressures to help it stay higher in its travel while open. When the open setting was employed things were dandy, but when firmed up for the climbs a lot of the small bump butter essential to maintaining a good climbing speed disappeared.

Despite claims on the part of almost every manufacturer of mountain bikes to have mitigated the constraints of physical reality, there is, and always will be, a compromise involved when creating a bike that is intended to climb as well as descend. In the case of the Jekyll, with its emphasis on winning races which are only timed on the downs, the balance is clearly on the side of downhill speed. The Jekyll truly is a downhill sled that can be made to go up under pedal power in an above average manner. On the downs, just go fast and enjoy. Piloting the Jekyll is a joy. It responds to a spectrum of inputs and changes lines easily. I strongly suspect the Jekyll will go as fast as anyone can keep up. It should be noted however, that the Jekyll is not a playful, jumpy, or particularly poppy ride. This bike is focused on speed alone. That is it, getting to the bottom faster than anyone else.

Quick Spec Thoughts

Post: Reverb=sure bet, stealth is even better.
Brakes: Magura's MT7 brakes are capable; on trail the power was there and modulated.
Bars: In house carbon piece with a nice finish and ability to take impacts.
Wheels: The wheels feature in house hubs and WTB Team Issue i23 rims. They are strong and light enough for the task and help get the price down to that sub 8,000 price point that seems more reasonable the more you look at it. ("It's only a third of a half years pay!")
Cranks: Canondale Hollowgram with XX1 30T ring.
Drive train: The XX1 setup is becoming a standard and complements the Jekyll's other components well. On the Jekyll it offered more gears/advantage than needed in most situations while reducing the number controls at the handlebars.

The Take Away

The time I spent aboard the Jekyll gave the distinct impression of riding a purpose built racing thoroughbred. It is riddled with features that, in the proper hands, should be conducive to competing at a high level in enduro style events. For a rider such a myself, however, such a tech centered approach to the tasks of going up and down trails might be more distraction than needed. Furthermore, if playful, poppy riding is more your thing then you might find the planted, full speed ahead preferences of the Jekyll a bit disappointing. If your focus is on going down as fast as possible but getting to the top under your own power, the Jekyll deserves a look. Riders savvy to innovative engineering and technology aimed at helping them go faster should really take the Jekyll for a spin. This review was arranged through BikeSport in Bellingham Washington but there are Cannondale distributers scattered all over the world where you might be able to test one out too.

Enjoy the ride!