Reviewing a proven winner is no easy task. In the hands of mild-mannered Jérôme Clémentz, the 160-millimeter-travel carbon-fiber Jekyll has proven to be one of the most successful race bikes on the Enduro World Series. The SRAM-sponsored shredder races with a two-legged RockShox Pike fork, but enduro racers here in North America have had no problems racking up wins running the single-sided SuperMax Lefty that Cannondale specs on the bike, and what’s more, WTB/Cannondale sponsored Marco Osborne recently trounced all comers at the Mammoth Mountain US ProGRT national DH race on his SuperMax-equipped Jekyll 27.5 Carbon Team. Proven performances earned in the exact realms for which Cannondale’s designers intended the bike to excel makes it tough for a reviewer, armed only with riding impressions and objective criticism, to beat it down to size.
Cannondale developed its Dyad RT2 in partnership with Fox
Racing Shox. The pull-shock configuration keeps the moving
bits bathed in oil and simplifies the rear suspension.Few components are more recognizable than Cannondale's Lefty
single-sided suspension strut. The 160-millimeter-stroke, carbon
fiber SuperMax has new, gravity-specific damping circuits.
Different Can Be a Good Thing
Criticism is one thing that Cannondale’s most successful trailbike has had plenty of – and very little of it is bounded in the realities of handling and performance. Most detractors point at Cannondale’s extensive use of non-standard components as their source of ire. Forget the fact that its 160-millimeter-stroke single-sided “fork” is lighter than any of its two-legged competitors and stiffer than many DH forks: “It just looks wrong.” Overlook that Cannondale’s headset never needs adjustment: “I can’t adjust it!” Neglect to admonish that Cannondale perfected the 30-millimeter aluminum BB standard with oversized, pressed-in bearings years before major players considered the concept: “It doesn’t have threads.” Forget that the Dyad-RT2 pull-shock turns a supple long-travel suspension bike into a sharp-pedaling short-stroke climber with a flick of a lever: “I can’t bolt a coil shock on that.” And, of course there is that one-sided front hub that allows the rider to change a tube or a tire without removing the wheel from the bike: “So, now I have a wheel that won’t fit on my DH or dirt-jump bikes?” For the record, the Jekyll is not the bike for those who dream that all production bikes and their associated parts will someday be globally cross-compatible, so customers can creatively mix and match parts like a Lego mountain bike builder’s kit.
For the open minded, Cannondale’s Jekyll is one of the few truly integrated bicycle designs – a well-appointed, carbon-framed, 160-millimeter-travel technical trail shredder that delivers race-winning performance and handling. The Jekyll’s non-standard parts were developed by Cannondale to permanently resolve nagging problems related to performance, efficiency and reliability that contemporary bike and component makers were either patching up or ignoring entirely. For example: Rather than providing a compromise shock tune with a lockout or traction option, the Fox-made Dyad RT2 shock provides two separate shock systems, each with its own damping and spring rate – a 160 millimeter circuit, tuned for technical sections and descending and a 95-millimeter option with a stiffer spring rate and slower rebound for pedaling and climbing.
That said, Cannondale is not fixated upon using dedicated components merely for the sake of differentiating its products. Look beyond the Jekyll’s dedicated shock, “fork” and headset arrangement, and the remainder of its components are items that most would expect to find on a premier enduro racing bike: WTB i23 rims, DT Swiss hubs, Schwalbe Hans Dampf tires, a SRAM XX1 drivetrain, a RockShox Reverb Stealth dropper post, Magura MT-7 brakes and a Gravity 740-millimeter carbon handlebar and 50-millimeter aluminum stem combo. Built accordingly, the complete medium-sized Jekyll Team, at only 26.86 pounds (12.21kg) ready to rock, is lighter than most trailbikes with much less suspension travel. MSRP for the top-drawer Carbon Team reviewed here runs $7580 USD, with and sizes offered in small, medium. Large and X-large. More affordable models range from the $6170 Carbon 2, to a pair of aluminum-framed models: the $3900 Jekyll 3 and the $3250 Jekyll 4.
Jekyll 27.5 Carbon Team Details:• Frame: Impact-resistant ballistic-type carbon construction, 160/95mm travel, single-pivot swingarm suspension, X-12 through-axle system, external cable routing, ISCG 03 tabs.
• Wheel diameter: 27.5-inch
• Fork: Lefty SuperMax, 160mm stroke, Carbon upper, aluminum lower, external rebound and lockout
• Shock: Dyad-2, Air-sprung, two chamber, remote-controlled pull-shock, 160mm or 95mm travel options with separate low-speed rebound controls. “Enduro” high-speed compression tune.
• Headset: Cannondale integrated 1.5-inch pressed-in type
• Bottom bracket: Cannondale BB30 press-in type
• Drivetrain: SRAM XX1 eleven-speed with Cannondale Hollowgram BB 30 aluminum crankset, 30-tooth XX1 chainring.
• Brakes: Magura MT6 with 180mm rotors
(MT7 four-piston brakes are the current spec)• Wheels: WTB i23 Team rims, DT Swiss 305 hubs, and DT Swiss Competition spokes.
• Seatpost: RockShox Reverb Stealth dropper post, 100mm stroke.
• Weight: (Medium size tested) 26.86 pounds
(12.21kg)• Sizes: Small, medium, large. X-large.
• MSRP: $7580 USD
• Contact: Cannondale USA
ConstructionCannondale says that it makes the Jekyll’s carbon chassis using a special high-modulus material that is used by armed forces where armor protection is necessary – which implies that it has a higher degree of impact resistance than more commonly used high-strength carbon. With two decades of carbon fiber bicycles under their belts, Cannondale’s designers are not afraid to profile the Jekyll’s frame tubes as narrow or as wide as required. Up front, the frame’s oversized head tube contains Cannondale’s tried-and-true press-fit 1.5-inch headset system which requires no periodic maintenance or adjustments. The massive top tube tapers quickly to meet the slender seat tube, while the downtube widens dramatically to 85 millimeters midway to the bottom bracket to support the suspension’s carbon fiber pull-shock rocker link. Elsewhere, the single-pivot swingarm and seatstays are crafted in semi-rectangular shapes to maximize stiffness and strength without taking up valuable real estate where drivetrain components and DH-width tires must pass.
Hollow, 15-millimeter-diameter axles are used throughout the Jekyll’s rear suspension and the sealed ball bearings are widely spaced to maximize lateral stiffness and minimize the effects of free play, however miniscule, that naturally occurs as all bearings wear over time. The axles are clamped to the outer segments of the suspension rocker link and swingarm to further secure the system against unwanted flex and also to simplify disassembly and maintenance.
At the rear of the bike, Cannondale designed massive, hollow carbon dropouts that house a pair of sealed ball bearings at each seatstay pivot, where clevis-type seatstay attachments further strengthen the pivot junctions. The aluminum derailleur hanger also attaches to the carbon dropout with a sturdy clevis mount. Cannondale employs the Syntace X-12 through-axle system which is secured with a six-millimeter Allen key. Threads on the drive side and a tapered collet on the left side lock the axle securely to the swingarm.
Practicality and ease of maintenance may have been the motivations for Cannondale to choose (with one exception) to route the Jekyll’s shift housings and brake hoses externally on the frame. Clean looking screw-in aluminum guides collect the two hoses and one housing that run to the bottom bracket on the underside of the downtube, where a tough rubber frame guard does double-duty, protecting the control conduits from injury. The remote hose for the bike’s RockShox reverb Stealth dropper post tucks into the seat tube though a rubber grommet. Oddly, even though there is an empty, fourth slot in the downtube guides, the remote cable that operates the Dyad-RT2 shock is internally routed through the downtube. The only explanation is that Cannondale’s design team were not committed to a one-by drivetrain and made the call to leave a spot for a future front derailleur housing.
Geometry tweaks to make the Jekyll 27.5 a more capable AM/enduro bike include a longer wheelbase and a slacker, 67-degree steering angle for high speed stability; slightly longer top tubes across the sizing range to compensate for its 50-millimeter stem, and a steeper seat tube angle to enhance climbing ergonomics. The offset of the Jekyll’s Lefty SuperMax has also been increased to 50 millimeters to match the bike’s steering geometry with its mid-sized, 27.5-inch wheels.
Detail oriented riders may appreciate that the simple profile of the Jekyll allows room inside the frame for a full-sized water bottle, and that the right chainstay has a large molded silencer/protector. Near the bottom bracket, a bonded stainless steel grind-guard prevents a derailed chain from destroying the carbon swingarm. Strangely, Cannondale chose the earlier, ISCG-03 mounting pattern for its dedicated chainguide tabs – but it’s there, nonetheless, for those who want the added security. Finally, if you absolutely need a front derailleur, Cannondale sells a direct-mount adaptor that fits threaded mounts on the right swingarm pivot – a handy item for any racer with a drivetrain sponsor that is keen on front mechs.
Dyad RT2 Pull-ShockCannondale worked out a new, high-flow compression circuit and tuned the Jekyll’s Dyad RT2 shock to work especially well on fast, technical descents that are typical of European enduro courses. As previously mentioned, in lieu of a lockout or a low-speed compression boosting circuit like Fox and RockShox use, the Dyad’s remote handlebar lever can switch the pull-shock between two fully functional 95-millimeter or 160-millmeter-travel modes.
Those who want to check out the inner workings of Cannondale’s Dyad RT2 pull shock should check out
Matt Wragg's Q&A on the subject. The short version is that the Dyad offers two separate damping and spring-rate functions in one shock mechanism. The pull-shock arrangement is not necessary to make the Dyad function properly, but it simplifies the suspension’s mechanical design and the damper benefits greatly by having all but one of its seals continuously lubricated. Dyad shocks have three chambers: the central pull-shock is basically a pump. When the suspension pulls on the pump shaft, depending upon where the remote lever is located, the pump forces shock fluid into one or both of the adjoining chambers.
Each of the side chambers has an internal floating piston
(IFP) and the air space that the floating pistons create functions as the shock’s air spring. In the long-travel mode, the pump fills both chambers and because the combined volume of the air springs is at its maximum, the Dyad shock’s spring rate is very linear. In short-travel mode, one chamber is closed off, which causes the pump to push a larger volume of fluid into a smaller air space. The combined effects create firmer damping, a sharply rising spring rate, and about a 50-percent reduction in the shock’s travel. Separate low-speed rebound circuits allow riders to fine-tune their rear suspensions for both short and long-travel modes. Small-bump sensitivity is tuned by adjusting the pressure of the Dyad’s negative air spring – an IFP located in the lower section of the pump.
While deciphering the Dyad’s workings can make many readers dizzy, the damping controls are all the same bits that one finds in conventional shocks Fox Racing Shox partnered with Cannondale to engineer the Dyad RT2 and it has proven to be a reliable system. Cannondale also has done diligence by opening authorized service centers that can maintain and tune them. Two important Dyad RT2 facts that prospective Jekyll owners should know is that it should be run with at least 30-percent sag in the longer-stroke position and that you’ll need to bring the special high-pressure shock pump that Cannondale provides if you want to do trailside adjustments. Dyad shock’s normal pressures begin at 300psi
(about 20.7 bar), which is the top of the red zone for a standard shock pump.
Three Things to Know About the Lefty SuperMaxHow it manages to be torsionally rigid: The Lefty’s inverted tubular stanchion tube is necessary to provide a sealing surface. Inside, the stanchion is rectangular and instead of sliding on bushings, it rolls on four rows of needle bearings trapped between the stanchion and matching tracks in the Lefty’s carbon fiber upper. Unlike sliding surfaces like conventional fork bushings, the Lefty’s needle bearings roll freely with minimal lubrication. Additionally, its four-sided tracks arrest torsional flex far more effectively than the wimpy arches and oversized axles that are used to prop up the stiffness of conventional forks.
Conventional damper: Inside the Lefty is a pretty conventional damping cartridge, similar to what you may find in many 160-millimeter forks. The 2015 SuperMax on our test bike has a new high-flow compression piston and both its compression and rebound valve stacks are tuned for higher speeds and proper descending. Two-legged forks typically use one side for hydraulics and the other for the air spring. The Lefty, however, splits the real estate inside the strut, with the damping cartridge occupying the upper section and the air spring housed in the lower, stanchion end. The damping cartridge requires only one special tool and is easily removed from the top for tuning or service.
Removing the wheel: The Lefty’s aluminum front axle is tapered, so it requires a matching hub. Many top wheel makers offer Lefty-compatible front wheels and hubs so Jekyll owners need not be concerned about future upgrades. There is no need to remove the wheel to change tires or fix a flat, but when you do have to remove the Lefty wheel, you’ll first need to unscrew the two fine-threaded 8mm screws that fix the brake caliper to the Lefty’s stanchion about two revolutions. The caliper mount will then lift off the screws and the brake rotor, which will in turn, allows the hub to move off of the axle. Unscrew the hub from the end of the axle with a five-millimeter Allen key and be sure to keep the hub and the exposed axle squeaky clean, because the bearings will be exposed and their inner races are a precision fit over the axle. After you reinstall the front wheel, replace the caliper mount. As long as you didn’t squeeze the front brake lever, the counter-sunk heads of the caliper retention screws should re-center the brake pads where you left them.
(Left)
Loosen the two screws on the bottom end of the Lefty's caliper mount and the entire assembly will lift off the rotor. The Lefty's hub is removed with a 5mm Allen key and the screw remains in place on the hub to make reassembly easier. Push the big red rebound dial down to unlock the "fork." Push the blue button and the dial pops up and locks-out the Lefty.
Specifications
|
Release Date
|
2015 |
|
Price
|
$7580 |
|
Travel |
160mm |
|
Rear Shock |
Dyad RT2 pull-shock |
|
Fork |
Lefty SuperMax 160mm |
|
Headset |
Cannondale HeadShok Si |
|
Cassette |
SRAM XG-1199, 10-42, 11-speed |
|
Crankarms |
Cannondale Hollowgram, SRAM XX1, 30T chainring |
|
Chainguide |
NA |
|
Bottom Bracket |
Cannondale BB30 |
|
Pedals |
NA |
|
Rear Derailleur |
SRAM XX1 |
|
Chain |
SRAM XX1, 11-speed |
|
Front Derailleur |
NA |
|
Shifter Pods |
SRAM XX1 |
|
Handlebar |
Cannondale C1 riser, carbon, 740x15mm |
|
Stem |
FSA Gravity Light, 1.5", 31.8, 50mm |
|
Grips |
Cannondale lock-on |
|
Brakes |
Magura MT6 (Tested), MT7 (spec'ed) |
|
Wheelset |
Cannondale custom |
|
Hubs |
DT Swiss 350 rear, Lefty front |
|
Spokes |
DT Swiss Competition |
|
Rim |
WTB i23 team |
|
Tires |
Hans Dampf, Snakeskin Trailstar, 27.5x2.35" tubeless ready |
|
Seat |
WTB Silverado Team Volt, CroMo |
|
Seatpost |
RockShox Reverb Stealth |
|