CANNONDALE JEKYLL CARBON 1 29 MOUNTAIN BIKE REVIEW
Review by Drew Rohde
Photos by Dusten Ryen
Cannondale’s Jekyll Carbon 1 is the top spec’d enduro mountain bike in Cannondale’s refreshed lineup, and we couldn’t wait to get that beautiful, color-changing paint dirty. Along with that attention grabbing paint, what draws an equal amount of attention to the Jekyll is the bike’s high pivot suspension, guidler wheel and unique shock mounting location.
The 2020’s have only just started but they have been transformative for mountain bike suspension platforms. There’s been a huge influx of higher pivot locations to produce more rearward axle paths that theoretically deal with the impacts better in rough terrain. Cannondale realized the benefits of the high pivot movement and set about designing the new Jekyll enduro machine to adopt some of their positive traits and make a machine that’s as happy on the racetrack as serving daily enduro duties. Since we filmed our Dissected feature, we’ve been putting the hurt on our Jekyll for the last few months in the high desert, and it’s time to share our verdict.
QUICK HITS
• 165mm Mid-High Pivot Horst Link Suspension
• HTA 64
• STA 77.5 (effective)
• REACH 475 (Large)
Price: $4,500/ £4,800 /€4,999(Jekyll 2) –$6,100/ £6,750 /€6,999 (Jekyll 1)
Website: Cannondale.com
THE LAB
For the new Jekyll, Cannondale went back to the drawing board to produce a purpose-built machine for “high speed mobbing”; whether it be at an enduro race on the world stage, or sessioning the local bike park. The Cannondale Jekyll specs include 29” wheels on both ends, the carbon fiber-only frame pairs 165mm travel out back with a 170mm travel, 38mm chassis fork, to offer serious capability for aggressive gravity riding.
There’s plenty to talk about with how Cannondale designed the Jekyll, and we covered them all in great detail here, in our Dissected Feature and interview with Cannondale. To briefly summarize that feature, the most obvious talking point is the suspension platform Cannondale selected. Rather than hopping on board the high single-pivot bandwagon, Cannondale instead used the familiar Horst link suspension design with a raised main pivot, producing a mid-high pivot system that afforded them increased control over the kinematics to produce the ride characteristics they sought after. The result is an axle path that features a healthy amount of rearward travel, but not quite as extreme as others. Just at mid-stroke, the path arches forward towards the start point at bottom out. Cannondale hoped to reduce the drawbacks that a higher pivot can produce, and we think they did. This mid-high pivot design is paired with a steel “Guidler” idler pulley/chain guide combo that sits concentric to the main pivot and reduces the effects of chain growth on the suspension performance. Cannondale didn’t stop at their new platform design though, with size-specific kinematics that should produce the same great handling characteristics for riders of all sizes.
The resulting kinematic with the Guidler in place gives anti-squat levels of around 100% at sag in the larger cassette cogs, which progressively reduces as you move down the cassette. This anti-squat drops off through the travel, to improve bump absorption when pedaling without sacrificing efficiency on smoother terrain. Anti-rise sits at roughly 65% at sag and also drops through the travel to improve suspension recovery on bigger compressions when braking, at the sacrifice of reduced geometry preservation. The leverage curve changes significantly with the frame size, with the small frame’s 13% progression through to the extra large’s 20% progression. This is done so that riders of different sizes and weights can achieve full travel and have an optimal experience. Regardless of the frame size, harder hitting riders will be best served by an air shock and some volume spacers, but a coil shock should still be suitable if desired.
The Cannondale Jekyll 1 29 has an exclusive carbon frame with CNC’d aluminum links and the aforementioned steel Guidler. To position the shock exactly where they wanted it, Cannondale created the “Gravity Cavity”, which sees the downtube split into a twin-spar design and nestles the shock in the center. This concentrates the bulk of the frame weight into the lowest and most central position, giving a lower center of gravity that should yield greater stability and maneuverability. Of course, the downside to that shock placement is its proximity to debris and the ease of accessing it for tuning purposes. To address that a large plastic guard serves to protect the shock from damage and dirt ingress, with provisions made to allow water and debris to escape.
The rear hub and drivetrain are offset with Cannondale’s AI (Asymmetric Integration) system, which improves spoke bracing angles and tire clearance but requires a specially dished rear wheel. Otherwise, things are as you would expect on a ‘22 frame with a tapered integrated headset and BSA BB, save for the lack of SRAM’s UDH hanger that we’d love to see it come with.
Geometry on the Jekyll is modern without going ultra-long and features their proportional response approach to tailor the rear center length to each size of rider to maintain weight balance between the wheels. Across the S-XL size range, the head angle is 64°, effective seat tube angle is 77.5° and the bottom bracket sits 30mm below the axles. The reach figures range from 425mm to 510mm, with the large sporting our preferred 475mm figure, and the stack goes from 625mm to 652mm. Seat tubes are relatively short on small to large, ranging from 390mm to 445mm, but the XL sees a 500mm seat tube to cater best to the longer-legged riders. The rear center length starts at 430mm on the small frame and increases progressively to 450mm on the XL. Wheelbases total 1,193mm on the small through to 1,311mm on the XL, with our large coming in at 1,264mm, which should offer a reasonable blend of stability and agility.
Cannondale offers customers three options for purchasing the Jekyll: a $3,700 frame with Float X2 shock; or a choice of two complete bikes from the $4,500 Jekyll 2 to the $6,100 Jekyll 1 build tested. The Jekyll 2 features an entry level build kit offering, with a Rock Shox ZEB Select fork paired with a Fox Float DPX2 Performance EVOL shock, Shimano Deore 12-speed gearing and M6120 brakes, a WTB STX i30 rim on Shimano MT400 wheelset, and an in-house alloy cockpit with a TranzX dropper.
The Jekyll 1 tested is a considerably more premium level kit for the discerning shredder, with a Fox 38/Float X2 factory suspension combo; SRAM GX Eagle drivetrain and CODE RSC brakes on 220mm front and 200mm rear rotors as standard; a WTB KOM Trail i30/Formula hub wheelset; and in-house carbon bar and 170mm dropper. It’s great to see Cannondale offering a budget build on their flagship enduro machine, but we’re sure glad we got to test the higher spec build.
THE DIRT
If you read our “First Impressions of the Cannondale Jekyll 1” at the end of our Dissected Feature then you’ll recall we were impressed and looking forward to lots more miles aboard this enduro-ready mountain bike. Compared to other high pivot bikes like the recently reviewed Norco Range and GT Force, the Cannondale Jekyll 1 29 bicycle is a strong contender. In some areas we’d say it’s better than the rest and then in others it’s not our favorite. Hopefully what you can take away from the following is what parts of the performance are most important to you and which areas you’re willing to compromise.
Climbing any of the high pivot bikes in our fleet requires some extra effort, and there’s no denying that they’re slower up the hill. At 35.5 pounds, it’s a few pounds lighter than the Range and arguably has a smoother feel while pedaling. It’s close in weight to the GT Force and climbs nearly as well. So, for a high pivot bike we’d say it’s average, which means for non-high pivot bikes it may be comparably sluggish.
On flatter, less challenging trails the Jekyll feels livelier than some rigs like the Range, but not quite as spritely as the Trek, YT or Canyon enduro offerings. It still moves around well and is far from cumbersome in the grand scheme of things, but you should be aware that Cannondale made this bike to navigate a specific type of terrain. If you’re not regularly charging that type of terrain, a shorter travel option is likely a better call.
We were quite surprised at how the Cannondale Jekyll performed on flow trails and jump trails. Pleasantly so. Yes, it has a lengthening wheelbase, albeit not as drastic as others, which can still be an issue for snaking tight berms at high speeds where you want to press and pop in and out of corners. However, on longer turns and bigger lips, the Jekyll did a very good job of maintaining speed and popping off the ground. It’s stable enough to inspire confidence, yet can also be whipped and moved, and made for some very fun play laps on our favorite jump lines. To put it shortly, the Jekyll is probably the best jumping high pivot bike we’ve ridden to date.
Once it came time to put this enduro bike in enduro terrain, it got even better. The Cannondale Jekyll is extremely comfortable at high speeds and while in a standing, attack position. All of our testers remarked on how quickly they felt comfortable aboard the Jekyll 1. When the trail pointed downhill, its ability to get up to speed and hold it wide open was impressive, especially when you factor in its reasonable agility on slower and tighter terrain. The mid-high pivot seems to be this crew’s favorite, as it doesn’t have quite as drastic compromises from the excessively growing rear end lengths, but still offers some of the benefits of a rearward axle path when it comes to tackling the chop.
If you’re a rider who’s regularly looking for speed on the trail but wants something with pleasant handling characteristics outside of the tape, the Jekyll could be a great machine for you. This mountain bike does a very good job of taking the sting off the big hits and smaller chatter and lets you look further down the trail with confidence. It’s a composed ride that offers stability and loves to rail bigger corners and float over chunder.
Overall, the Cannondale Jekyll 1 29 specs are problem free as a whole, but that’s not to say it’s a perfect bike. The choice to spec EXO+ tires must have been driven by the overall bike weight figure, as they’re certainly not what we’d choose to spec for enduro racing. The shock cavity makes adjustment difficult and adds an extra step, as well as making it more difficult to clean after a sloppy ride. Otherwise, the bike ran relatively quiet aside from some minor idler “whirring” when the chain became a little dirty, and we had no issues or complaints with the remainder of the spec. The value proposition, at $6100 for this build tested, seems reasonable, if not mind-blowing.
The Wolf’s Last Word
The Cannondale Jekyll 1 29 is a pretty badass enduro bike all around. We don’t need to spend a lot of time telling you that mountain bikes have grown more specific in their intentions, and because of that, riders should really evaluate the reality of their trails, demands and where they want their next bike to excel.
While we do really like the Jekyll overall, it’s not a perfect bike and we think there will be a few areas of concern for some riders. That said, Cannondale has done a great job making the Jekyll a very worthy adversary to any gnarly trail it encounters. When it comes to high pivot bikes, we like the mid-high platform a lot as it gives some of the benefits without such a drastic rearward axle path. Our testers were impressed with how such a capable downhill-ready bike can jump, bounce and play on the flow trails. For the right rider, this bike is one we would definitely recommend. 
Price: $6,100/ £6,750 /€6,999
Weight: 35.6 pounds
Website: Cannondale.com
SPECIFICATIONS
CHASSIS
Frame: Carbon fiber | 165mm
Fork: Fox Float Factory 38 | 170mm
Shock: Fox Float Factory X2
COCKPIT
Brakes: SRAM Code RSC, 220F/200R Centreline rotors
Handlebar: Cannondale 1 Riser, Carbon, 30mm rise, 8° sweep, 5° rise, 780mm
Headset: Integrated Sealed Bearing, Tapered
Saddle: Fabric Scoop Shallow Elite
Seatpost: Cannondale DownLow Dropper, 31.6mm, 125mm (S), 150mm (M), 170mm (L-XL)
Shifter: SRAM GX Eagle; 12s
Stem: FSA Grid 35, 35mm
WHEELS
Wheelset: WTB KOM Trail i30 TCS/ (F) Formula 15mm / (R) SRAM MTH 700, XD; 110/148
Front Tire: Maxxis Assegai, 29 x 2.5″, 3C compound, EXO+
Rear Tire: Maxxis Minion DHR II, 29 x 2.4″, EXO+
DRIVETRAIN
Bottom Bracket: SRAM DUB Threaded
Cassette: SRAM XG 1275; 10-52T
Cranks: SRAM X1 Eagle, Boost, DUB, 30T
Derailleur: SRAM GX Lunar Eagle; 12s
We Dig
That color!
Stable yet fun
Loves going fast
Eats chunder
Jumps well
Proportional Response geo
We Don’t
Exo + rear tire
Slow climber
Shock tuning access is tricky
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