Cannondale Scalpel Review | The Scalpel flexes all-new carbon muscles

The not-so-minor details

Product

2021 Cannondale Scalpel Carbon 2

Contact

PSI Cycling

https://www.psicycling.com.au/

Price

$8,299 AUD

Weight

11.06kg

Positives

- Smooth, comfortable and traction-rich suspension
- The Lefty Ocho is a dead-brilliant performer
- Powerful and efficient riding position
- Dual water bottle capability
- The neat STASH tool system

Negatives

- The Lefty Ocho is heavier than its competitors
- Razor-sharp handling isn't as planted on the descents
- Wheel removal is a bit faffier than usual
- Slow engaging rear hub

Wil reviews the 2021 Cannondale Scalpel

Few of you reading this won’t already be familiar with the Scalpel name. First launched in 2001, the Scalpel emerged as a very lightweight, very efficient, and very short-travel full suspension XC race bike designed to woo elite riders away from their hardtails. Cannondale believed that full suspension could be faster, and the Scalpel was its 80mm travel ticket to World Cup glory. That first model, with its soft-tail suspension design that relied on carbon flex-stays and a tiny shock that sat vertically behind the seat tube, was an iconic bike for Cannondale and also incredibly innovative for its time. As well as its hybrid alloy & carbon construction, it featured the original Lefty (a head-scratching, bamboozler of a product in its own right), and it came with tubeless wheels, disc brakes and a 2×9 drivetrain. It doesn’t sound like much now, but at the time, that was proper cutting edge stuff.

Fast-forward two decades and Cannondale is set to launch an entirely new Scalpel – the 8th generation of the US brand’s heirloom race bike. Well, there’s actually two new Scalpels, but we’ll get to that in a bit, along with a detailed rundown of the Scalpel I’ve been testing for the past month. First though, let’s take a look at the most technically advanced Scalpel yet, and find out how Cannondale can boldly proclaim that this is the lightest full suspension bike on the market.

Check out our video review of the 2021 Cannondale Scalpel here:

The Cannondale Scalpel – what’s new?

It’s been four years since the last Scalpel launched at the Cairns World Cup in 2016, and as you’ll see, a lot has changed since then. At its core the Scalpel remains as a lightweight 100mm travel XC race bike. It shares a familiar shape to its predecessor with a top tube mounted shock and dual water bottle capability, and it continues to be built around 29in wheels and the bizarre single-sided, single-crowned Lefty Ocho. Go a little deeper though, and you’ll discover a new suspension layout with a quirky flex-stay, modernised geometry, and an entirely new carbon fibre layup that Cannondale states is 200g lighter than the old frame.

2021 cannondale scalpel carbon 2
After plenty of teasing, the 2021 Cannondale Scalpel has finally arrived!

Flip that link

The big performance story with the new Scalpel is its new suspension design. The upper shock link no longer swings from the top tube like it did on the old frame. Instead, the rear shock is driven by a tiny alloy link that mounts to a forward strut partway up the seat tube. It doesn’t sound like much, but it has completely changed the suspension behaviour. The new Scalpel has a much higher starting leverage rate (2.85:1 rather than 2.23:1), and it’s vastly more progressive too.

Like the latest Habit trail bike, the Scalpel also gets a size-specific approach to suspension kinematics. This means there’s actually a different leverage ratio, anti-squat and anti-rise levels for each of the four frame sizes. The designers achieve this with slight variations to the location of each pivot point – the shock dimensions and alloy link are the same for every frame.

2021 cannondale scalpel carbon 2
The rear shock still mounts to the top tube, but the way it’s driven has changed.

Hold on, where’s the pivot?

The Scalpel uses a one-piece carbon swingarm, but Cannondale says it’s now built around a Horst Link four-bar suspension platform. As you’ve probably spotted already though, there are no actual bearings anywhere near the rear dropout. Instead of a traditional pivot, there’s an incredibly thin section of carbon fibre along the chainstays. This concentrates about 6-7° of flexion at a specific point just forward of the dropouts, emulating a Horst Link pivot.

Doing so in this fashion however, means that the Scalpel isn’t lumped with the usual weight penalty that comes with a typical four-bar suspension design.

Flex stays are of course nothing new. But where the new Scalpel differs from its predecessor, and indeed most popular XC full suspension bikes on the market like the Specialized Epic, Trek Supercaliber, Canyon Lux and Scott Spark, is that the flex doesn’t occur through the seatstays. According to Cannondale, putting the flex point on the chainstays creates a more active suspension system that is less influenced by braking and pedalling inputs, compared to a traditional single-pivot arrangement. Doing so in this fashion however, means that the Scalpel isn’t lumped with the usual weight penalty that comes with a typical four-bar suspension design.

In some ways Cannondale is kind of coming full circle, as earlier 26in iterations of the Scalpel did use carbon chainstays that flexed throughout the range of travel. Indeed up until 2013, the Scalpel didn’t even have a main pivot – ALL of the flex occurred through the chainstays, which in hindsight, is a bit bonkers really. Anyway, I digress…

2021 cannondale scalpel carbon 2
Solid carbon fibre flex-stays sit in place of a conventional pivot.

Is it strong?

It does look freakishly delicate, but while the rest of the chainstays and seatstays are hollow, that flattened section is actually 100% solid compressed carbon fibre. It’s also very wide in order to limit lateral flex. In fact, Cannondale says that wide strip of carbon is so much stiffer than a traditional pivot that it was able to strip out some carbon from the rest of the swingarm to prevent the back of the bike from being too stiff.

To see exactly how tough it is, Cannondale’s engineers developed a specific torture rig to test the flex stays. This rig repeatedly applied 150% of bottom-out force (over three tonnes) at the rear axle over hundreds of thousands of cycles. Not only did the test frames survive, it got to the point where the machine had to be turned off so the engineering team could move onto other projects.

Along with real-world testing on the trail, the team also developed a custom flex-stay swingarm for Josh Bryceland’s personal Habit, and gave it to him to try and destroy. He couldn’t destroy it.

2021 cannondale scalpel carbon 2
As well as being lighter and simpler than a pivot bearing, the flex-stays are also stiffer laterally too.

Cannondale Scalpel weight

Now we all know that weight isn’t everything, and even the most die-hard XC racers are coming to understand that too. But Cannondale also admits that if you’re not hitting a particular figure, you’re not part of the conversation – irrespective of how good your bike may be.

To ensure the Scalpel is part of the conversation, it comes with an impressive 1,910g claimed weight. That’s for a Medium frame including the rear shock, thru-axle, hanger, protection and cable ports. This sees a hefty 10% weight drop over the old Scalpel frame, which is impressive.

This sees a hefty 10% weight drop over the old Scalpel frame, which is impressive.

Worth mentioning here is that the headline weight figure is specifically for the Hi-MOD frame. This is the name that Cannondale gives to its flagship carbon frames, and it basically refers to the use of a higher-modulus carbon fibre. Cheaper Scalpels come with a standard carbon frame that is otherwise identical while being 250g heavier (2,160g claimed).

*Fun Fact* – this isn’t actually the lightest Scalpel that there has ever been. That mantel goes to the 2012 model, which supposedly weighed just 1,590g including the rear shock. Yikes! Of course that Scalpel was built around 26in wheels, had significantly shorter tubes, and it also didn’t have a main pivot. I think we can all agree that full suspension bikes have improved a lot since then, even if they have gotten a bit heavier. Anyway, I digress again…

2021 cannondale scalpel carbon 2
Dual bottle ready. Once you’ve had two, it’s VERY hard to go back to one.

How does that compare to the competition?

So here’s the thing – when it comes to claimed weights, the Scott Spark is still currently the lightest full suspension frame on the market. Here we’ve listed several popular XC race bikes in order of their claimed frame weights, which includes the rear shock, axle and hardware;

So according to Cannondale, the Scalpel came out lightest. Surprised? No? Us neither.

However, we’re told that during the Scalpel’s development, the engineering team purchased a bunch of those bikes to test them in-house while also validating frame weights. Here’s what they came up with;

So according to Cannondale, the Scalpel came out lightest. Surprised? No, us neither. What is a bit of a surprise though is the Scott Spark, which is regarded as being the lightest on the market, and we’ve seen examples that weigh a lot closer to Scott’s claims. Yet this sample was apparently 150g heavier. I dug a little deeper, and it turns out that Cannondale’s sample frame didn’t have the carbon link – it had an alloy link instead, which does seem a little unusual. Of course without all of those frames in front of us, we can’t exactly verify anyone’s claims so it’s kind of a moot pissing match. Either way, we love that Cannondale is throwing shade at its competitors, and we look forward to its competitors throwing some shade in return.

Catty weight games aside, I’ll also point out that the Scalpel does come with a rather incredible 138kg rider weight limit, along with a limited lifetime frame warranty for the original owner. A disposable race-only piece, this is not.

2021 cannondale scalpel carbon 2
Along with the new frame, the Scalpel gets fresh geometry to bring it right up to date.

Modernised geometry

Making the 200g weight drop even more impressive is the fact that the Scalpel’s frame is considerably longer than its predecessor. Reach has grown by 10-15mm across the four frame sizes, and the head angle has slackened out to 68°. The seat angle has also steepened to 74.5° and the BB now sits 3mm lower too. However, chainstay length is relatively unchanged at 436mm.

Also unchanged is the 55mm fork offset for the Lefty Ocho. Whereas other brands are moving to offsets around 42-44mm, and indeed the new RockShox SID is only available with a 44mm offset, Cannondale is sticking to its OutFront geometry concept (slack head angle, long fork offset). I’ll go into more detail about how that plays out on the trail shortly.

2021 cannondale scalpel carbon 2 lefty ocho
The Lefty Ocho has a 55mm offset, which is quite a bit longer than what some other brands are using.

Scalpel gets Boosted

Yup, the Scalpel finally moves to a 148x12mm Boost rear hub. However, the back end is still built around Cannondale’s Asymmetric Integration (A.I) offset concept. This sees the rear hub and the whole drivetrain offset away from the frame a further 3mm than a regular Boost setup, which achieves a wider 55mm chainline (regular Boost is 52mm, and Super Boost is 56mm). It’s also why the bike comes with Cannondale’s own Hollowgram crankset and chainring that matches the custom chainline.

With the rear hub sitting 3mm further off centre, the rim is dished 3mm back the other way to keep it aligned with the front wheel. Cannondale says the A.I dish helps to even out spoke tensions to create a more durable wheel, and the wider chainline allows for a beefier chainstay yoke, while still affording clearance for a 2.4in wide tyre. And pretty much any Boost wheel can be re-dished to fit.

You’ll still find an 83mm wide PF30 bottom bracket shell, which provides a suitable home for the crank’s 30mm alloy spindle.

2021 cannondale scalpel carbon 2
The seat tube flares out to create a large pocket for the main pivot. It’s all very beefy down there.

You’ll still find an 83mm wide PF30 bottom bracket shell, which provides a suitable home for the crank’s 30mm alloy spindle. It also creates a huge junction point between the downtube and the dramatically flared-out seat tube, which houses the main pivot inside its ‘chainstay garage’. It’s all very big and robust looking down there.

Up top, the Scalpel does ditch the 1.5in head tube in favour of a more conventional tapered head tube, and that’s because the Lefty Ocho uses a standard tapered steerer. On the note of frame standards, the rear brake calliper mounts to regular 160mm post-mount tabs, rather than the Flat Mount standard that the previous Scalpel utilised.

Sneaky STASH

Cannondale has also built the Scalpel with a conventional metric shock, which mounts to a wide pivot that’s tucked into the equally wide and flattened top tube. This allows for a near direct path for the lockout cable that disappears into the top tube, and it also maintains sufficient clearance inside the mainframe for two water bottles. Further selling the pack-less dream, Cannondale has introduced a clever integrated STASH tool system in the middle of the downtube. This plastic sheath holds a tiny Fabric multi-tool and a Dynaplug Racer tyre plug – both of which are included on all Scalpels bar the cheapest model. A rubber strap allows you to hold a CO2 canister or a pump.

2021 cannondale scalpel carbon 2
The Scalpel will accommodate two water bottles inside the mainframe, and it also gets a clever STASH tool system.

This plastic sheath holds a tiny Fabric multi-tool and a Dynaplug Racer tyre plug – both of which are included on all Scalpels bar the cheapest model.

2021 cannondale scalpel carbon 2
You can access the internal cables underneath the tool holster.

Remove the tool holster, and you’ll discover a cutout in the carbon downtube. This ‘window’ gives you access to the internally routed derailleur cable and rear brake hose, both of which are lassoed up with a zip tie that anchors to the underside of the tool holster. The cables continue on their internal journey through the chainstays, with both popping out just before the carbon flex-stay.

The Cannondale Scalpel SE

With the last generation Scalpel, Cannondale introduced an SE model that came spec’d with a 120mm travel fork, a dropper post, and some burlier components to offer a more fun and versatile XC package for those who weren’t totally obsessed by racing. That concept continues with the new Scalpel, but Cannondale has taken it one step further this time round.

2021 cannondale scalpel carbon se 1
The Scalpel SE pumps up the travel to 120mm front & rear.

The Scalpel SE shares the same frame as the regular Scalpel, but instead of a 190x40mm shock, the SE comes with a 190x45mm shock that is said to increase rear travel to 120mm. To balance it out, there’s a 120mm RockShox SID fork up front, and that kicks back the head angle to 67° and lifts the BB height by 13mm. It also slackens the seat tube angle, but only to 74°. This is because the regular Scalpels are spec’d with offset seatposts, while the SE comes spec’d with a 0mm offset dropper post. Completing the trail-ready picture are slightly wider 780mm handlebars, a shorter stem, and higher volume tyres.

Cannondale Scalpel price & specs

PSI Cycling, Cannondale’s Australian distributor, will be bringing four Scalpels to our shores. There’s a single Hi-MOD model, two of the regular carbon Scalpels, and one SE model, with prices ranging from $6,299 AUD to $10,999 AUD. As of right now, there are no plans for any alloy Scalpels – it’s carbon only for this speed wagon.

 

2021 cannondale scalpel hi-mod 1
The top-end Scalpel Hi-MOD gets a Lefty Ocho Carbon fork along with ENVE finishing kit, XTR brakes and shifting.

2021 Cannondale Scalpel Hi-MOD 1

2021 cannondale scalpel carbon 2
Equipped with carbon wheels and a Shimano XT groupset, the Scalpel Carbon 2 looks a mighty sharp for the privateer racer.

2021 Cannondale Scalpel Carbon 2

2021 cannondale scalpel carbon 3
As the entry-point into the range, the Scalpel Carbon 3 gets the same high-performance suspension design and Lefty Ocho fork.

2021 Cannondale Scalpel Carbon 3

2021 cannondale scalpel carbon se 1
Not so worried about grams? The Scalpel SE gets a dropper post, wider bars and 120mm travel front & rear to provide more fun and capability in a speedy package.

2021 Cannondale Scalpel Carbon SE 1

2021 cannondale scalpel carbon 2 wil buxton
The Scalpel doing what it does best – slicing and dicing through swoopy singletrack in the forest. This bike carves!

Testing the new Scalpel

Over the past month, I’ve been putting a load of saddle time into our 2021 Cannondale Scalpel Carbon 2 test bike. As well as being my first on-trail experience of the new Scalpel, it was also my first encounter with the intriguing Lefty Ocho.

Thankfully for a newb like me, there’s a handy fork setup guide just next to the brake calliper. For my 68kg riding weight, that saw 120psi recommended for the air spring, and 10 clicks of rebound damping from the slowest setting. To help you monitor travel use, there’s a discreet sag indicator on the inside of the lower cable guard, and a marking to show you when you’ve waxed all the travel. If you’re hitting full travel too often, it is possible to add a volume spacer inside the air spring. Cannondale calls these ‘Ramp Clamps’, and there’s one already inside the fork from the factory. You can remove this if you want a more linear feel, or you can add a second Ramp Clamp if you need more bottom-out support.

Over the next few rides, I steadily lowered the pressure until I was down to 180psi, which put me right on the recommended 25% sag figure.

For the rear shock, Cannondale recommends running 10-11mm of sag, which equates to 25-27% of the shock stroke. Of note here is that you’ll want to use a ruler to measure displacement of the O-ring on the shock stanchion. This is because the shock stroke is 40mm, but the total length of the exposed stanchion is actually 45mm. So the O-ring won’t go all the way to the end at full travel.

Cannondale has put another handy setup guide for the rear shock on the seat tube. The guide suggested 200psi for my weight, but within the first ride I found it to be quite a bit firmer than I wanted. Over the next few rides, I steadily lowered the pressure until I was down to 180psi, which put me right on the recommended 25% sag figure. Rebound was set one click faster than halfway at 8/14 clicks.

2021 cannondale scalpel carbon 2 wil buxton
At just on 11kg and with its fast-rolling Schwalbe tyres, the Scalpel Carbon 2 doesn’t hang about.

Bloody heck, this bike is F-A-S-T

First thing’s first. Weighing in at just 11.06kg, the Scalpel Carbon 2 isn’t exactly sluggish off the mark. That’s no doubt helped by the lightweight carbon wheels (1,690g confirmed) and fast-rolling Schwalbe rubber.

The tyres are very light (661g front & 674g rear) thanks to their thin and flexible casings. During setup, I found them to be a touch loose on the rim, which meant they required a burst of compressed air to get the beads to seat properly. I was also worried about pinch-flatting on my local trails which are very loose and rocky, so I set pressures relatively high at 25psi on the front and 28psi on the rear. That prevented any punctures throughout testing, but really the Racing Ray/Ralph combo is much better suited to softer, loamy trails. In their preferred environment on smoother singletrack deep in the woods, I was able to drop pressures down to a more malleable 23/26psi.

schwalbe racing ralph 2021 cannondale scalpel carbon 2
The stock Schwalbe tyres are very light at less than 700g each.

Cannondale Scalpel – fit & handling

Backing up the low rotational mass, the Scalpel offers an efficient, low and stretched out stance that means business the moment you swing a leg over. At 175cm tall, I’m riding a Medium size and it fits the bill perfectly. Cannondale has stuck on a 760mm wide flat-bar, which is big for an XC bike. You could always cut them down if you prefer, but I dig the broad hand placement and the stability it brings. Initially I wanted more upsweep, but once I learned to actively drop my shoulders and elbows, I came to appreciate the Scalpel’s purposeful riding position.

Keyboard warriors may wish for steeper, but I certainly haven’t.

And in terms of contact points, Cannondale has got this bike absolutely dialled. The ESI grips offer excellent vibration-damping qualities, and at 60g they’re also about half the weight of a lock-on equivalent. The snub-nose Prologo saddle is also superb. There’s less nose to get in the way on steep pinches, and it never once caused me any bother – even on longer multi-hour rides. It was also easy to get my preferred setback position with the Scalpel’s 74.5° seat angle. Keyboard warriors may wish for steeper, but I certainly haven’t. After all, this is an XC bike with just 100mm of travel. And because there’s less suspension sag, the seat tube doesn’t slacken out a whole lot on the climbs in the first place.

2021 cannondale scalpel carbon 2
Cannondale has spec’d 760mm wide bars and soft ESI silicone foam grips for the Scalpel. It’s a great combo.

It’s razor-sharp, but not too deadly

Comfort is built upon thanks to the Scalpel’s active suspension, compliant chassis and low-profile carbon rims. It doesn’t ping about like some other XC race bikes, and I found it to be smoother in the rough compared to the Canyon Lux I tested recently.

Make no mistake though, the steering up front is razor-sharp. Even though the Scalpel is pretty slack, the 55mm fork offset results in a fairly tight trail figure of 90mm. That’s about the same as a Scott Spark RC (90.9mm), though shorter than the Specialized Epic (94mm) and the Trek Supercaliber (96mm). The shorter trail figure gives a lighter steering feel and a propensity to change direction easily, so the Scalpel feels eager to corner. It also delivers a more aggressive turn-in that took me a few rides to adjust to, having mostly ridden short fork offsets lately.

The OutFront geometry does stick the front hub quite far ahead, and that requires you to actively weight the front wheel.

Once you’re on tight and twisty singletrack, this bike absolutely hums. It loves weaving through the trees, and it slices and dices slow-speed technical sections with incredible efficiency. The quick steering means it’s easy to make last-minute corrections, and since the front wheel is capable of cutting a tight arc, you’re rarely left wrestling with understeer. The OutFront geometry does stick the front hub quite far ahead, and that requires you to actively weight the front wheel. This feels pretty natural though, since the Scalpel encourages a low and forward riding position, so keeping the front tyre sticking is rarely a problem for assertive racers.

2021 cannondale scalpel carbon 2 wil buxton
The OutFront geometry does require you to lean forward to maximise grip on the front tyre.

The steering can feel too sharp though, and you’ll certainly need to concentrate on sketchier descents. If you’re not steadfast on the grips, the front end can feel a bit wriggly. The wide bars and slack head angle help here for sure. But while the long front centre reduces the sensation that you’ll be sent over the bars, the short trail figure and relatively sparse tyre tread mean that it doesn’t take much for the front wheel to be kicked off-line. On rough high-speed trails littered with loose baby-head sized rocks, I certainly had a few ‘moments’. Still, it’s a testament to the quality of the overall chassis, suspension and the confidence-inspiring Lefty Ocho in particular that I never came a cropper.

Smooth suspension performance

Bucking the usual trend for an XC race bike, the Scalpel’s suspension is smooth, active and really comfortable on rough terrain. This is partly due to the low anti-squat levels. Most XC bikes aim for over 100% anti-squat, so that the suspension actively stiffens up under pedalling. Instead, Cannondale’s engineers deliberately tuned the new Scalpel’s kinematics to produce around 90% anti-squat at the sag point, and it drops off further as you go through the travel. The primary goal here is to better decouple the rear shock from pedalling inputs.

Instead of getting hung-up on square edges that disrupt your pedal stroke, the Scalpel carries terrific momentum, floating over choppy sections of trail.

Get the Scalpel onto rough, undulating singletrack, and you can see exactly why it’s been designed this way. Even under power, the suspension remains active with no discernible pedal feedback. Instead of getting hung-up on square edges that disrupt your pedal stroke, the Scalpel carries terrific momentum, floating over choppy sections of trail. No, it isn’t exactly a big squishy All Mountain bike. But given there’s only 100mm of travel, the suspension is thoroughly effective, and the way the rear wheel is able to track the ground on rough descents feels not unlike a proper multi-link bike, like the Mach 4 SL or Blur.

2021 cannondale scalpel carbon 2 wil buxton
The active suspension design ensures excellent traction even under hard pedalling inputs.

The back end is also plenty stiff thanks to the huge main pivot junction and the broad carbon flex-stays. The seatstays are also significantly bigger and boxier than the pencil-thin tubes you’ll find on the Lux or Spark, and that does seem to make a positive difference to torsional rigidity at the rear axle. There’s little complaining from the chassis on hard compressions, and indeed the progressive suspension design gives you great support. While it tends to be pretty easy to bottom out an XC race bike, it takes a big impact to hit full travel on the Scalpel, which manages its suspension impeccably well.

Combined with the responsive steering and low front end, the Scalpel will have you consistently seeking out the tricky singletrack climbing option over a boring fireroad.

Traction is also excellent on technical ascents. Combined with the responsive steering and low front end, the Scalpel will have you consistently seeking out the tricky singletrack climbing option over a boring fireroad.

It’s not crazy firm under power

With the active suspension design, the Scalpel isn’t as firm at the pedals as its single-pivot competitors. For that reason, you do have a handy dual remote lockout at your disposal, which allows you to firm up the fork and shock simultaneously with a single lever push. With either open or locked positions, the Fox remote works well, and the lever action is surprisingly light. Worth noting is that the suspension doesn’t fully lock – there’s still a few millimetres of squish, and the blowoff circuits mean both the fork and shock will compress if you hit something really hard.

2021 cannondale scalpel carbon 2
The dual remote lockout firms up both the fork and shock simultaneously.

If you are looking for a stronger platform without having to resort to the lockout lever, it’s possible to increase low-speed compression damping on the Lefty, and I also found adding 10psi to the rear shock stiffened things up considerably. This is a handy tuning approach for racing on smoother courses, allowing you to emulate the feel to a traditional race bike. Bear in mind that running higher pressures will make it harder to access full travel though, and it also reduces the suspension’s ability to keep you floating on technical chunder.

In comparison the Scalpel is more active, and on rougher terrain that makes it more effective.

As such, I generally preferred keeping the shock set at the recommended sag, while utilising the lockout lever anytime the terrain warranted it. This isn’t a dissimilar approach to the Spark with its TwinLoc remote system, though it is quite different to the Brain-equipped Epic and short-travel Supercaliber, both of which prioritise uncompromising pedal efficiency 100% of the time. In comparison the Scalpel is more active, and on rougher terrain that makes it more effective.

The Lefty Ocho

I’ve also been super impressed by the Lefty Ocho fork, which is a genuine engineering marvel. How Cannondale has squeezed a self-equalising air spring, volume spacers, and an adjustable damper into a single fork leg with a single crown, I’m not sure I’ll ever fully comprehend. But that’s ok. What I can comprehend is how well it rides. I wouldn’t say the Lefty is any more supple off the top compared to a Fox 32 or a RockShox SID, and indeed small-bump compliance is pretty comparable between all three. As the impacts get harder and faster though, the Lefty’s stout structure really starts to shine.

2021 cannondale scalpel carbon 2
The Lefty Ocho is a bizarre looking single-legged, and single-crowned fork. It’s a bloody impressive feat of engineering too.

Slamming the front wheel into off-camber roots and rock ledges, there is noticeably less twisting through the chassis. Not only does this help with steering precision, it also reduces binding internally, allowing the fork to better absorb impacts even when it’s being smacked around in every which direction. This is something you’ll notice when dumping the bike into a blown-out high-speed corner that’s littered with braking bumps and missing chunks of earth. Even when it’s being subjected to bending forces though, the Lefty continues to slide smoothly. It really does track the ground remarkably well.

This seems to be counter-intuitive given the Lefty Ocho’s strange single-legged and single-crowned structure, but there’s actually a lot going on to make this fork stiffer than a conventional suspension fork.

As well as preventing twisting, the bearings ensure the Lefty slides smoothly even under bending loads.

For a start, the upper tube and crown are forged from the same big hunk of alloy, and that attaches to a thick tapered steerer tube. Internally, the sliding surfaces of the Lefty aren’t actually round. While the stanchion tube is round at the bottom, further up inside the fork it moves to a triangular profile that has a vertical strip of needle roller bearings on each of the three flat sides. It’s this triad of roller bearings that the stanchion slides up and down on, rather than round bushings that a traditional fork uses. As well as preventing twisting, the bearings ensure the Lefty slides smoothly even under bending loads.

Aside from the proprietary hub it requires, and the fact that there’s no easy way of fitting a mudguard, the downside of the Lefty Ocho is that is heavier than the competition.

Creating a stronger interface with the front hub and wheel, the lower stanchion tube and tapered axle are also forged from a single blob of alloy. This differs from a normal fork, where the axle is independent of the lowers. Even when bolted down, there is simply more opportunity for twisting when you place a round axle inside round dropouts. In comparison, the solid axle on the Lefty can’t rotate.

Aside from the proprietary hub it requires, and the fact that there’s no easy way of fitting a mudguard, the downside of the Lefty Ocho is that is heavier than the competition. The fork on our test bike came in at 1,731g on the scales, which is kind of porky for an XC race fork. Compare that to a Fox 32 Step-Cast (1,406g) or a RockShox SID SL Ultimate (1,326g), and that’s a hefty penalty for the gram counters.

Worth noting that Cannondale does make a carbon version of the Lefty Ocho that’s said to weigh just 1,446g, but that fork only comes on the most expensive Hi-MOD Scalpel.

2021 cannondale scalpel carbon 2 wil buxton
The Lefty Ocho tracks incredibly well, improving front-end confidence on the Scalpel.

Lefty Ocho vs Fox 32 SC

That’s a great question you pose! To provide an answer, I also tested our Scalpel with a Fox 32 Step-Cast fork. I was curious to see how the two forks would compare directly, and I was also interested to see how the Scalpel would handle with a shorter 44mm offset.

Since the Scalpel now uses a tapered head tube, fitting a conventional fork is a lot easier. The Fox fork had an immediate impact on the scale, dropping the complete bike weight down to 10.8kg. Unfortunately it wasn’t quite a perfect test, since I had to use a different front wheel. However, everything else remained the same, allowing me to get a good impression of the difference by riding the same test loop back-to-back.

This tends to happen more on violent off-camber hits when you’re deeper into the travel, and it’s in this scenario where the stiffer Lefty Ocho is clearly a superior fork.

While the Fox 32 SC does have excellent small-bump sensitivity, it is noticeably twangier compared to the Lefty Ocho – both torsionally and fore & aft. It tracks well for the most part, but certainly on bigger impacts, you can feel the 32 SC’s upper tubes binding inside the bushings as the legs are bent under load. This tends to happen more on violent off-camber hits when you’re deeper into the travel, and it’s in this scenario where the stiffer Lefty Ocho is clearly a superior fork. Given the significant weight difference though, perhaps the Fox 34 Step-Cast would provide a more fair comparison.

2021 cannondale scalpel carbon 2 fox 32 step-cast
The tapered head tube makes it a bit easier to fit a conventional fork on the front of the Scalpel, so I put one on there to see what it was like.
2021 cannondale scalpel carbon 2 fox 32 step-cast
As well as comparing the Fox 32 SC to the Lefty Ocho, I wanted to see what the handling was like with a shorter 44mm offset.

Chassis differences aside, the 32 SC did calm down the Scalpel’s sharp steering. While the head angle stays the same, the shorter offset actually increases the trail (from 90mm to 100mm), and this strengthens the front wheel’s ability to self-stabilise. On the trail, the shorter offset delivered a more planted feel on the descents, since the front wheel is inclined to remain pointing straight ahead. Also noticeable was the improved front-end traction, which is a simple by-product of bringing the tyre contact patch 11mm closer to the rider. Compared to the 55mm offset on the Lefty, I didn’t need to consciously weight the front end as much, and that gave a more predictable ride quality when traction was at a premium.

The fact that there is very little fore and aft flex means the Lefty holds its line well, while also better preserving its dynamic head angle compared to a flexier fork.

The downside of going to a shorter offset? The steering didn’t have quite the same laser-accuracy, which I noticed on slow-speed technical sections where it took more effort to negotiate the front wheel around obstacles. And on really tight switchback climbs, the 32 SC couldn’t carve as sharp of an arc as the Lefty.

Now I will admit that the change in handling is reasonably subtle – to the point where most riders would really need to try both back-to-back to fully appreciate the differences. And I think it’s a testament to the quality of the Lefty Ocho that the front of this bike feels so confidence-inspiring in the first place despite the low trail figure. The fact that there is very little fore and aft flex means the Lefty holds its line well, while also better preserving its dynamic head angle compared to a flexier fork.

2021 cannondale scalpel carbon 2
The Lefty Ocho is a very impressive fork on the trail, and it offers genuine performance advantages over traditional fork designs.

In general though, those chasing the most responsive steering possible will appreciate the Scalpel’s OutFront geometry, particularly for racing on tighter and twisty singletrack. This is a race bike after all, and if you’re already coming from a bike with a 51mm offset, the light steering is going to feel pretty familiar. For me personally, while I preferred the performance of the Lefty Ocho, I did favour the calmer feel of the shorter offset. It requires a little less concentration on the descents, something that can be of benefit to marathon racers and long distance trail riders. From that perspective, those folks may want to consider the Scalpel SE, which comes spec’d with a 120mm RockShox SID fork and a 44mm offset.

As polarising as the Lefty Ocho is in the looks department, there’s no denying how well it rides on the trail, and it’s a bit of a shame that this experience is currently limited to the Scalpel and F-Si hardtail.

While I do like that Cannondale is sticking to its guns with the OutFront concept when nearly every other brand is going the other way with fork offset, if I was being cynical, I’d suggest that it’s probably an expensive proposition for Cannondale to retool the Lefty Ocho with a shorter offset. Still, I’d be interested to see if that option is offered in the future. I’d also love to see Cannondale offer up a longer travel option too. As polarising as the Lefty Ocho is in the looks department, there’s no denying how well it rides on the trail, and it feels a bit of a shame that this experience is currently limited to the Scalpel and F-Si hardtail.

2021 cannondale scalpel carbon 2 xt 1x12
The component package on the Scalpel Carbon 2 is top-notch. No complaints from the 1×12 Shimano XT drivetrain or those sweet Hollowgram cranks.

Component highs & lows

Overall the Scalpel Carbon 2 delivers an excellent race-ready package right out of the box. There is nothing to complain about with the Shimano XT groupset, which is mostly flawless and really not that much heavier than XTR. The brakes are perhaps a little bitey for a lightweight XC race bike, but they are solid and they’re also easy to setup and maintain.

Cannondale has saved weight by spec’ing its own Hollowgram crankset, which came in at just 535g for the hollow arms, alloy BB30 axle, and 34T chainring on the Scales Of Broken Dreams™. That’s about 100g lighter than an XT crankset, and within spitting distance of XTR. We’re told that the cranks are actually new for this year, with slightly stiffer arms and self-extracting bolts that makes them easier to remove.

Though the wheels and tyres performed just fine throughout testing, engagement from the rear hub is slow at 15°. And while it’s nice to see DT Swiss internals, I’d rather Cannondale have spec’d the Star Ratchet instead of a pawl-based freehub mechanism, which seems a bit cheap on a bike costing nearly $8K.

Take care during the removal and installation procedure, since the mounting stubs are covered in grease, and you’ll be mere millimetres away from the rotor.

While I’m being picky, wheel installation and removal itself is a little faffy too. With the Lefty, you’ll need to remove the brake calliper entirely before you can unbolt the front hub from the axle. Cannondale has made this easier with a ‘quick release’ system that is comprised of a push-button and a 5mm hex bolt, which when unlocked, removes the brake mount and calliper entirely from the fork. Take care during the removal and installation procedure, since the mounting stubs are covered in grease, and you’ll be mere millimetres away from the rotor.

cannondale scalpel axle
The stepped axle and open dropout is meant to provide quicker wheel removal, though in practice it’s kinda faffy.

At the back, Cannondale has also tried to make things easier with the ‘Speed Release’ dropouts. The non-drive side dropout is actually open, and there’s a corresponding step in the thru-axle that allows you to drop the rear wheel out of the frame without having to remove the axle entirely. It works, but installing the rear wheel is less speedy as you need to line up that stepped axle perfectly with the split dropout before the hub will slot into place. Personally I’d just rather see a closed dropout with a regular axle. Oh, and if anyone at Cannondale is listening, let’s make the front and rear thru-axles both 5mm or both 6mm – not one of each please.

2021 cannondale scalpel carbon 2
The chainguide is neat, just make sure the main pivot is torqued to spec to keep it in place.

Though everything was otherwise tight and quiet throughout testing, I did have two specific issues. The first was some rubbing from the chainguide, which mounts directly to the main pivot. Under hard suspension compressions, the mount would rotate backwards slightly, and over the course of a ride it would rotate far enough that it would eventually rub on the chain in the lower gears. The fix was simple – loosen the main pivot, reposition the guide, and torque the main pivot to spec. Since doing so, it hasn’t budged.

We’ve been informed that this is a non-issue on production bikes, which all have the correct sized pivot pin.

About halfway through testing, I also discovered a small amount of play coming from the lower shock mount, which presented itself as a light ‘clunk’ at top out. In speaking with Cannondale, this play turned out to be a result of an undersized pivot pin that was ever-so-slightly loose in the shock’s DU bushing. We’ve been informed that this is a non-issue on production bikes, which all have the correct sized pivot pin. I do have a replacement pivot pin and DU bushing on the way to me though, so once I have that on the bike and confirm it has rectified the issue, I’ll be sure to update the review accordingly.

UPDATE: We’ve since received the replacement lower shock pivot pin and hardware, which as you’ll see in the photos above, is clearly stamped with a “2” on the outside face of the pivot bolt. You’ll also be able to tell just by looking at the comparative photo that the tolerances are a lot tighter – the new hardware doesn’t have any side-to-side slop like the original did.

With those tighter tolerances, the replacement shock did feel slightly firmer for the first few rides. As everything settled in though, the smooth suspension action returned, albeit without any of the play that the original hardware presented. And even after several weeks of riding with the new production pin, everything has remained tight and quiet. Of course that’s not the same as six months of flat-out riding and racing, but I’m confident that the new hardware has solved the issue.

2021 cannondale scalpel carbon 2 wil buxton
The Cannondale Scalpel is remarkably smooth for an XC race bike, and that pays dividends the rougher the trail gets.

Flow’s Verdict

Cannondale has built an absolutely ripping XC speedster in the new Scalpel. It is no doubt a sharp handling machine, but if you’re eyeing off a position on the podium, you’re likely to appreciate the near-telepathic steering. Competitive types and long distance haulers will also love the dual bottle capability and neat STASH tool system. There’s also good versatility in the chassis with the option to fit a dropper post, a 120mm fork and up to a 2.4in wide rear tyre. If any of those float your boat though, and you tend to buy your own champagne rather than win it in races, then it’ll be worth taking a good look at the Scalpel SE. If it’s raw speed you’re after though, then the Scalpel Carbon 2 has that in spades.

While the lovely carbon frame is significantly lighter than its predecessor, the new Scalpel is more technically capable thanks to its vastly improved suspension performance. The active design means it isn’t quite as snappy at the pedals as some of its competitors, but on rough terrain the Scalpel is smoother, more comfortable and it builds speed incredibly well. Add in the superb Lefty Ocho and the modernised geometry, and you have a technically proficient handler that thrives on taking the more challenging route both up and down the mountain. Thumbs up to Cannondale, because this bike is an absolute corker.

2021 cannondale scalpel carbon 2 wil buxton
The low weight is impressive, but it’s the improved geometry, suspension performance and Lefty Ocho that really caught my attention. It all adds up to a seriously fast package on the trail.

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