Review: 2019 Cannondale Jekyll 29-1

The Jekyll’s sleek carbon front section and linkage-driven, single-pivot rear suspension boasts 150 millimeters of wheel travel. Cannondale collaborated with Fox to develop the DPX2 EVOL “Gemini” remote actuated shock, which switches the travel from 150 to 120 millimeters and firms up the ride. Simple looking bridgeless seatstays drive the shock via a massive rocker link that arcs over the bottom bracket, creating the negative space dedicated to the Jekyll’s vertically mounted water bottle. In the Cannondale tradition, its front section is carbon fiber, while the rear suspension is welded aluminum, although you’d have to look closely, because the dual-pass welding appears seamless. The profile of the Jekyll looks different, but it’s the high-quality, well-thought-out kind of different.

With an MSRP of $6850 USD, the top shelf Jekyll 29-1 has a killer component selection – one that won’t have you scrambling for an upgrade until you’ve ridden it into the ground. It’s suspended by a Fox Factory 36 fork with the FIT Grip2 damper, and its low-slung frame ensures room for 150mm-stroke Fox Transfer dropper post. Other key players include a SRAM Eagle XO1 drivetrain, powerful Code RSC brakes, and combat-proven Stans Flow Mk3 aluminum rims shod with Maxxis Minion DHF and DHR tires. Cannondale-branded items fill out a roomy cockpit that highlights the Jekyll’s aggressive geometry

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Construction and Features

Cannondale may have stepped back from their penchant for wild designs for the moment, but the Jekyll 29’s chassis has a few creative touches that stand out. Its massive rocker link plays two roles. It moderates the shock rate changes that short links create, and it makes room for the Jekyll’s vertical water bottle placement.



No provision is given for a front derailleur, which eliminates the need for a tragically offset drive-side chainstay. The Jekyll’s swingarm takes the shortest distance between the axle and the frame, and picks up a significant measure of tire clearance along the way. Up top, the seatstays are bridgeless, which makes room for tires up to 2.5 inches with 29-inch wheels and also facilitates the Jekyll’s relatively short, 442 millimeter chainstays. Oh, and there are ISCG 05 mounts on its press-in bottom bracket shell if anyone can remember what those are for.

Geometry & Sizing

Cannondale was one of the first mountain bike brands to adopt steep seat tube angles, but the likes of Pole and Nicolai have raised that bar considerably higher. The Jekyll’s 75-degree seat tube is mild by contemporary standards, but sporty enough to keep most riders happy on the climbs. Up front, 65 degrees is in the slack department for a 29er’s head tube angle. Cannondale pairs it with fork that has 42mm of offset.

Reach is on the tip of almost every new bike buyer’s tongue, and bike makers have been pushing the limits. Our medium-sized review bike is listed at 441 millimeters, which is ample, but not excessive. In fact, Cannondale reduced the reach numbers on the Jekyll 29 compared to the 27.5" wheeled version by approximately 7mm.

The Jekyll's chainstays measure in at 442 millimeters, and the bottom bracket height is not rock bashing low, at 355 millimeters (14”). Keep in mind that that number is with a 150mm fork - going with even more travel up front will create and even higher bottom bracket.

Suspension Design

The overarching story about the Jekyll’s kinematic design is that it was reportedly crafted to keep the rear suspension supple and near its sag point under braking. That’s a clever trick to pull off with a single-pivot rear suspension, but it can be done. Swingarm pivot placement and proper ride height play commanding roles in that equation, so getting your shock tune right may be key to the Jekyll’s happiness.

Cannondale and Scott have been long-time proponents of handlebar-remote suspension-travel devices. Like Scott’s, Cannondale’s Gemini employs a dual chamber air spring that shortens the Jekyll’s rear-wheel travel from 150 millimeters, to 120 and raises the ride height of the rear suspension. The combined effect is excellent for climbing, because it emulates a steeper seat tube angle and provides the extra support needed to compensate for the rearward weight shift. The downside is the necessary addition of the Fox-made Gemini control lever on the handlebar.



The shock itself is a Fox Float Factory DPX2 EVOL that both Cannondale and Fox say, has a very light damping tune, which indicates that the suspension has a low leverage ratio. If that’s the case, I’d anticipate that small modifications in the spring pressure and damping adjustments will have a larger impact on the bike’s performance.

Cannondale chose a Fox Float Factory 36 fork (with the impressive FIT Grip2 Damper) that matches the rear-suspension’s 150-millimeter travel. I like the trend to bias the bike's travel, with slightly more travel in the fork, but the Jekyll’s big wheels should make an additional 10 millimeters of squish up front a non issue.

Jekyll 29-1 Build

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I rode the Jekyll 29 in a variety of conditions, including mud, snow, and hero dirt. Most of my saddle time, however, was typical for home: fast-paced, rocky, rutted, dusty and slick as hot buttered hell. My first ride was a high-speed beater – primarily downhill over rock gardens that often command a toll in paint, rubber and flesh. Near the bottom, my once-sensitive-to-adjust shock was toast. I could screw the clickers all the way in and they had little damping to offer in compression and rebound.

I really had to hit something hard to achieve full travel and I wanted the rear suspension to ride lower in the turns, so I experimented with reduced spring-pressure settings. Surprisingly, 160psi (just 10 psi less) dropped the shock sag to 40 percent and rode too softly. I inched back up to 168, which is where I left it for the duration.

The Fox 36 fork was more familiar to me. I ended up with 68psi in the spring, with low-speed compression set two clicks in, high-speed compression five clicks in, and low-speed rebound, five clicks out.

Climbing

I found the Jekyll to be an easy climber, both for its efficient feel at the cranks and for its agility up technical climbs. The cockpit is roomy and I liked the weight balance, which kept the front wheel on the ground without eroding rear-wheel traction. Its 2.4-inch Maxxis rear tire and WT-type casing put a lot of rubber to the ground, which further enhanced climbing grip. Cannondale specs a smaller, 30-tooth chainring, which allows riders with sub-pro-cross-country legs take full advantage of the Jekyll's portfolio of climbing skills to top challenging pitches that many would be forced to push.

Reduced offset forks are the rage these days, and 29ers with slack head tube angles benefit most from that discovery. Cannondale's paring of a 42-millimeter offset with the Jekyll's 65-degree head tube angle keeps its steering light and responsive at speed, but while climbing steeper grades, the steering can get wiggly. That was bothersome initially, but I adapted to the quirk after about a week in the saddle.

Descending

Get its shock and fork balanced and the Jekyll will reward you on the downs with intuitive control and trustworthy cornering traction. The rear suspension seems to be the key player in the handling equation. If it rides too high, the bike feels a little unstable down the rocks and roots. Too soft and it bogs down in the turns and bounces out of high-G compressions. It's not hard to get the suspension right, and it's well worth the effort to spend a couple of rides experimenting with spring pressure and damping dials.

the joy of its handling is more about flow. So often, "destroying the trail" is the accolade used to describe a top descender. By contrast, what I liked about this bike is that it tends to sew all the features together. Easy or challenging, downhills blended into one seamless experience.

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How does it compare?

Scott's Genius 900-series gives us a rare opportunity to compare similarly spec'ed all-mountain/enduro bikes that share nearly identical technical features. They both are 29ers from vanguard bike brands. Both have a Fox-made dual-travel shock and both share the same, 150-millimeter suspension travels and 65-degree head angles. Performance wise, the two bikes should ride similarly, because on paper, they are so close. That said, the winner is the Cannondale Jekyll 29-1.

Builds: For the high intensity riding styles these machines are touted for, only the Cannondale is a needs-nothing build. Cannondale's $6800 Jekyll 29-1 slots between the MSRP of Scott's Genius 900 and 910. The Cannondale has an aluminum rear section. The Scott 900 sports full carbon, while the 910 shares the Jekyll's aluminum tail end. Component-wise, Cannondale wins the battle with a SRAM XO1 Eagle drivetrain (Genius 910s are GX/XO1 hybrids). The Jekyll's Fox 36 fork trumps the Scott's 34 and while the Scott Nude shocks are based upon Fox's in-line dampers, Cannondale's Gemini is built around the more desirable Fox DPX-2 reservoir shock. Syncros wheels are one of the better house brands made, but the nod goes to the Jekyll's Stans Flow rims and more capable Maxxis Minion tires. Compare brakes and the Jekyll wins again with SRAM Code RSC versus Scott's choice of either Shimano XT or SRAM Guide RSC. Good news for both brands is they chose 200 millimeter rotors up front.


Performance: Both designs have 65-degree had angles, and corrected fork offsets. Reaches for medium sizes are stated a 441mm for the Jekyll and at 439mm for the Genius, while their seat angles are 75 and 74.5 degrees respectively. Scotts have an 11.5mm lower bottom bracket height, and shorter chainstays (438mm for the Genius and 442mm for the Jekyll). On the dirt, however the Cannondale feels noticeably more collected at speed and out corners the Scott by a noticeable margin. The Scott's rear suspension is less fussy to set up, but it never attains the Cannondale's deeper feel at full travel.

Climbing controls: Scott's TwinLoc remote suspension control affects both the fork and shock, has three modes and more ergonomically engineered lever. If you sprint out of the saddle often, Scott's TwinLoc is like the push-to-pass button on a Formula 1 car. Cannondale's Gemini system only affects the shock and its measure of pedaling firmness is far less dramatic. Climbing fast-paced smooth trails is the dominion of Scott, and if I pedaled any distance on prepared roads to access trails, I'd probably choose TwinLoc. On the dirt, however, Cannondale's Gemini offers twenty millimeters more travel in the short mode, and correspondingly more traction. I also like that the Gemini only has two options and that I could descend well enough in short travel mode. Less worries about being in the correct mode equals more fun.

Technical Report

Real wheels: Hard to go wrong with aluminum Stans Flow rims and WT Maxxis Minion DHR and DHF rubber. Cannondale's choice to go with a race-proven wheelset was the right one.

Gemini remote system: Not a huge fan of handlebar clutter, and the Gemini lever is butt-ugly. That said, I came to enjoy the more upright saddle position and firmer pedaling while climbing.

New frame design: Two thumbs up for the Jekyl's more conservative chassis. It has a good balance between pedaling stiffness, with just enough give in the frame and wheels to erase the fatigue that the stiffer-is-better mentality has heaped upon us.

SRAM Code RSC brakes: The more I ride these, the more I wonder why SRAM didn't market their DH brakes to trail bike makers a long time ago.

Is there a Jekyll 29-1 in Your Future?

Cannondale fans who have been waiting for the brand to modernize the suspension and handling of their top trail bikes will find more than they had hoped for in the the Jekyll 29's performance. Big wheels and the promise of a stable ride offer up a busload of confidence when speed meets technical terrain. Ratboy proves otherwise in his latest edits, but the no worries nature of the new Jekyll's handling may not capture the imagination of aggressive, slash and dash type riders.

Pinkbike's Take