The Takeaway: It’s fast, it’s smooth, it’s heavy, and it’s good.

  • Lefty Oliver suspension fork offers 30mm of travel.
  • Bosch Performance CX motor with assist up to 28mph
  • Three models priced from $5,800 to $9,000

Price: $5,800 (Topstone Neo Carbon 3 Lefty as tested)

Weight: 39.5 lb. (small)

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In 2016, I spent some time riding Cannondale’s Slate around Tuscon, Arizona. The Slate was a bit of a weird thing at the time: gravel equipment as we know it today was in its infancy, and the Slate was an aluminum-framed, 650b only, “New Road” bike with 30mm-travel dual-crown Lefty Oliver suspension fork. I thought the Slate was close to something interesting, but on the road, it was a pig compared to a road bike, and off-road it was hamstrung by its too-tall gearing and too-slick tires. I also thought the Lefty’s spring and damper performance lagged far behind what RockShox and Fox offered at the time. The Slate had things to like, but it also seemed like it needed more time to bake.

Four more years to bake, apparently. In many obvious ways, the Topstone Carbon models with the new Lefty Oliver are the spiritual successors to the Slate. But they are more fully realized than the Slate ever was.

—Five Cool Features—

cannondale topstone carbon neo lefty 3
Lefty Oliver

A single-sided Lefty Oliver with 30mm of travel smooths the ride.

Matt Phillips
cannondale topstone carbon neo lefty 3
Quick Change

The front brake is on a quick release for easier wheel removal.

Matt Phillips
cannondale topstone carbon neo lefty 3
Lock It Out

Lock out the fork for less movement.

Matt Phillips
cannondale topstone carbon neo lefty 3

The Bosch Performance CX motor offers assist up to 28MPH.

Matt Phillips
cannondale topstone carbon neo lefty 3
Smaller Wheels

The Neo 3 Lefty runs on 650b wheels, but also can be fitted with 700c.

Matt Phillips

The New Lefty Oliver

The Topstone Carbon’s 30mm of rear suspension is effective, but it begs for something up front to balance out the ride. That something is now here: a slimmed-down version of Cannondale’s Lefty Ocho upside-down, single-crown, single-sided, suspension fork.

The Lefty Oliver found on the Topstone offers 30mm of air-sprung and hydraulically damped travel. The claimed weight for the carbon version is 1340 grams, while the aluminum version weighs 1610 grams. It will fit up to a 650x47mm tire or a 700x45mm tire.

It uses a standard 1-1/8 to 1-1/2 inch tapered steerer, and if you like its look, you can buy the carbon version in the aftermarket for $1,500 and upgrade your existing Topstone Carbon. As far as sticking it on other gravel bikes, note that the Lefty Oliver has 55mm of offset, which might do funky things for your bikes handling if it was designed around a shorter offset fork (a typical gravel fork would be 45mm offset, give or take a few millimeters). This is how it stacks up against other gravel suspension forks: Fox’s 40mm travel 32 AX ( 700x40mm or 650x47mm clearance) weighs about 1315 grams and sells for $819, while Lauf’s 30mm travel Grit SL fork weighs 850 grams and sells for $990 ( 700x45mm or 650x53mm clearance).

cannondale topstone carbon neo lefty 3
The Lefty Oliver weighs 1610g in the aluminum version (shown), or 1340g in the carbon version.
Matt Phillips

Though it’s the shortest travel Lefty, it shares the signature features of Cannondale’s unique suspension fork. That includes the three-sided interface between the upper and lower legs claimed to prevent twisting, the three sets of needle bearings the fork rolls on as it cycles through its travel, and the tapered stub-axle that the proprietary bolt-on hub fits over. The single leg design does have a notable space challenge. The Lefty crams both the spring and the damper into the same leg—suspension forks from Fox and RockShox put the spring in one leg, and the damper in the other.

Compared to Cannondale's Lefty Ocho mountain bike forks, the Oliver gets a unique spring and damper tune. The spring is tuned to keep the fork riding near the top of its travel—with only 30mm available you want every bit at the ready. The damper has a bit of a “platform” tune intended to limit movement from rider inputs—should give it more of a traditional rigid fork feel on smoother surfaces. There’s also a lockout for hardpack and pavement, but a blowoff backs it in case you whack a bump.

One of the side benefits of the Lefty design is you can change a flat without removing the wheel from the bike. But if you do need to remove the front wheel, the Oliver has a quick-release brake caliper mount that’s easy to use, foolproof, and seems extremely robust. Also of note: the Oliver takes a flat-mount caliper(so do Lauf’s forks) which the Fox AX suspension fork does not.

As far as geometry goes, the Lefty Oliver has 55mm of rake, the same as the Topstone Carbon’s rigid fork. This ties into Cannondale’s OutFront geometry concept, which pairs a slacker head angle with a longer offset fork for to push the front wheel forward for a longer wheelbase and less toe-overlap, but keeps trail in check (a road-like 57mm in most sizes) to keep a light steering feel. It’s a touch longer than a rigid fork— I measured the Lefty Oliver’s axle to crown and got 407mm, which is 12mm longer than an Enve G-Series gravel fork.

Worth the Weight?

Here’s the thing about suspension: It weighs more than not suspension. But if done well, it has comfort, traction, speed, and control benefits that a rigid bike can’t match.

But the weight and complexity is something to consider. The lightest Lefty Oliver weighs over 1300 grams. A rigid carbon gravel fork weighs 500 to 600 grams (Enve’s gravel fork is 520 grams, claimed). The Oliver has seals and bearing, and a damper that needs servicing and you can’t mount things to the Oliver for bike packing or long rides.

cannondale topstone carbon neo lefty 3
Suspension has benefits, but is not without compromise.
Matt Phillips

But suspension has genuine benefits that can offset the added weight for some rider, and in many situations. We went through this with mountain bikes, and now it might be gravel’s turn. The suspension gravel bike may never overtake the category like full-suspension mountain bikes have in their world. Still, suspension gravel will, and should, exist as a viable alternative that excels in some conditions—just like the hardtail mountain bike does today.

And if you’re not a fan of the additional weight, expense, and maintenance penalties suspension incurs, or the non-traditional looks, don’t worry. We’re a long way from suspension—front or full—overtaking the gravel category. There are be plenty of traditional rigid gravel bikes to buy.

Topstone Neo Carbon With Lefty Models

Coinciding with the launch of the Lefty Oliver is the launch of the e-versions of Cannondale’s Topstone Carbon gravel bike. In the USA, there are three class-three models starting with the $5,800 Topstone Carbon Neo Lefty 3, and topping out with the $9,000 Topstone Carbon Neo Lefty 1. In the middle is the Topstone Carbon Neo 2, $6,500, which has a rigid carbon fork.

topstone neo carbon 1 lefty
The Topstone Neo Carbon 1 Lefty ($9,000)

All three models use the same carbon frame with the Topstone’s Kingpin rear suspension system (30mm of travel, dropper post, front derailleur, and rear fender compatible), the same Bosch Performance Line Speed motor with assist up to 28mph, and the same 500Wh battery.

The Lefty-equipped Topstone Carbon Neo models roll on 650b wheels with 42mm tires, while the Topstone Carbon Neo 2 with rigid fork rolls on 700c wheels with 37mm tires—this is also the lone 2x drivetrain model.

Topstone Carbon With Lefty Models

The launch of the Lefty Oliver brings with it an expansion of the Topstone Carbon range. There are still rigid-fork equipped models, but they now reside alongside two Lefty equipped models. Both Lefty models roll on 650x47mm tires and use 1x drivetrains.

The Topstone Carbon Lefty 1 ($7,500) runs the lighter carbon Lefty Oliver, a SRAM AXS 1x12 drivetrain, Cannondale’s SAVE semi-integrated stem and carbon bar, and has carbon rims.

topstone carbon lefty 1
The Topstone Carbon Lefty 1 ($7,500).

The Topstone Carbon Lefty 3 ($3,750) uses the aluminum Lefty Oliver, a Shimano GRX 1x11 drivetrain, and has a standard aluminum bar and stem, and aluminum rims.

Reviewed: Cannondale’s Topstone Neo Carbon 3 Lefty

The Topstone Carbon Neo Lefty 3 weighs nearly 40 pounds, has a motor that assists up to 28mph, knobby tires, and is essentially a full suspension bike. It’s not pretty, it’s a bit weird, but it’s a super good time.

The star of the show—the Lefty Oliver—works very well. As advertised, rider inputs don’t induce much motion, and it stays high in its travel. As a result, the steering feels about the same as a gravel bike with a rigid fork, and I didn’t feel the fork sinking through it’s travel when cornering on harder surfaces.

cannondale topstone carbon neo lefty 3
Cannondale suggests adding 10psi when running the Oliver on an e-bike.
Matt Phillips

The Oliver isn’t as supple off the top like a mountain bike fork, and it takes a bigger bump to initiate travel. For this reason, it’s easy to underinflate the fork if you’re used to how a mountain bike fork feels. Underinflation leads to a trap door effect: the Oliver holds itself up, but then blows through its travel when the platform is overcome. With the right amount of pressure, the Oliver transitions off its platform smoothly and does a great job smoothing out many bumps—better than the Topstone’s rear suspension. It provides noticeably more braking traction, cornering traction, and overall control, as well as improved comfort. Paired with the 30mm of rear travel, the Topstone Neo is a very smooth bike in many situations.

But the Oliver has just 30mm of travel, and when hung on the front of a 40-pound e-bike that assists up to 28mph, well, it’s easy to use all that travel up (even with the 10psi of additional pressure Cannondale recommends when running the Oliver on an e-bike). Though it worked well on single hits and many of the bumps found on many gravel roads, I found it was quickly overwhelmed by a series of braking bumps and square-edged rocks. It’s far superior to a rigid fork, but I also feel like it is far from the last word in gravel front suspension. I did not get a chance to ride the Oliver on the much lighter acoustic Topstone, though I suspect it may feel better without the additional mass of the ebike flying around.

cannondale topstone carbon neo lefty 3
Narrow/wide chainring teeth and an upper guide keep the chain secure on bumpy roads.
Matt Phillips

One thing that is without question though, is its steering precision. It’s stout and feels sharp and accurate, even on the front of a heavy ebike. Its fore/aft stiffness is especially exceptional: nary a twitch or wiggle from the front end even when hard on the brakes.

The performance of Bosch’s motors is well established. The Topstone Neo’s Performance Line Speed has good grunt and runs smoothly and reasonably quietly. It’s freaking fast too: climbing up a decently-steep hill at over 20mph fast. But this motor—most often used for road bike models—is so powerful that it becomes a bit of a handful off-road. It can be challenging to manage traction on looser surfaces, and it can accelerate so quickly that it feels like the proverbial bull in a china shop on tighter trails. The bike was smoother handling and easier to ride in some situations by turning it down to its lowest assist modes.

But with so much power and speed on tap, it does burn battery. Cannondale claims a maximum range of 79 miles from the 500Wh battery. But that will go down, way down, as you turn up the assist, or point it uphill. In sport mode—2nd to highest assist—I burned a full charge in about 49 minutes on a 12.6-mile climb with 32oo feet of gain.

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The rear end of the Topsone flexes to offer 30mm of travel.
Matt Phillips

The build on the model I tested—the lowest-priced Topstone Carbon Neo—was great. The Shimano GRX drivetrain shifted as it always does: smooth, fast, precise, quiet. The disc brakes were also smooth and easy to control, with plenty of power to slow this beast down. On pavement, the WTB Resolute tires feel pretty fast and roll quietly for such a knobby tire. On dirt and gravel, they provide excellent traction and good cornering grip with a very predictable breakaway. The tires and WTB rims also seem pretty tough—a good thing because on a 40-pound class 3 e-bike, you’re going to hit things hard.

But I’m a bit mystified why the e-version of the Topstone with Lefty gets 42mm tires while the unpowered Topstone with Lefty gets 47mm tires. I’d like to see the fatter tires on the e-bike too. I’m also at a loss to understand why the e-Topstone doesn’t get a bento-box mount on the top tube like the unpowered version.

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Fuel filler cap.
Matt Phillips

Though positioned as a gravel bike, the Topstone Neo is more versatile than that. I think suspension is practically essential for a class 3 e-bike. They’re heavy and fast: when you hit bumps, you wallop them, and they can unsettle a bike. With its effective front and rear suspension heavy-duty build, and speed, I think the Topstone Neo with Lefty would make a kick-ass multi-surface commuter bike. Plus, on hard surfaces and pavement, the Topstone is one of the livelier handling gravel bikes, so I think—with 700c wheels and skinnier tires—it might make a surprisingly excellent e-road bike.

The Topstone Neo with Lefty is a crazy bike. As one of my Bicycling colleagues commented, “There’s a lot going on. It’s...a bike with many features.” It’s fast, it’s capable, and it’s smooth (mostly). It’ll gobble up those gravel—and maybe road—miles and keep you comfortable and smiling for hours.

Cannondale Topstone Neo Carbon 3 Lefty Electric Bike - 2021

Topstone Neo Carbon 3 Lefty Electric Bike - 2021

Cannondale Topstone Neo Carbon 3 Lefty Electric Bike - 2021

$6,300 at REI
  • Fast—assists up to 28MPH
  • Smooth ride and extra control
  • Odd looking

Headshot of Matt Phillips
Matt Phillips
Senior Test Editor, Bicycling

A gear editor for his entire career, Matt’s journey to becoming a leading cycling tech journalist started in 1995, and he’s been at it ever since; likely riding more cycling equipment than anyone on the planet along the way. Previous to his time with Bicycling, Matt worked in bike shops as a service manager, mechanic, and sales person. Based in Durango, Colorado, he enjoys riding and testing any and all kinds of bikes, so you’re just as likely to see him on a road bike dressed in Lycra at a Tuesday night worlds ride as you are to find him dressed in a full face helmet and pads riding a bike park on an enduro bike. He doesn’t race often, but he’s game for anything; having entered road races, criteriums, trials competitions, dual slalom, downhill races, enduros, stage races, short track, time trials, and gran fondos. Next up on his to-do list: a multi day bikepacking trip, and an e-bike race.