I absolutely loved the aluminum Cannondale Topstone for what it was: a nicely spec’d, well-riding, off-the-shelf all-road bike that has Cannondale’s DNA with build options ranging from $1,050 to $2,100. It was a great bike at a solid price that didn’t skimp on the build kit or frame design. So when Cannondale launched the Carbon Topstone, with new passive suspension design, I was interested in seeing how the bike would ride. To come out with such an evolved design from the original Topstone, it had to be worth it, right? Well… it’s complicated.
Topstone Carbon
With build kits starting at $2,750 for the Topstone Carbon 105 and ranging up to $6,750 for the Topstone Carbon Force AXS kit, the barrier for entry is only $650 more compared to its aluminum predecessor for a completely different frame and riding experience. Whereas the aluminum Topstone solidified its capabilities with a no-frills aluminum frameset and a dropper post – on the model we reviewed – the Topstone Carbon has a lot more going on. Much of this design and technology is in line with what you’d expect from one of the largest bicycle manufacturers in the world and is a clear competitor with what other companies have offered in terms of ride dampening technologies. Where Specialized has taken on passive front suspension systems like the Future Shock with their all-road or gravel bikes, Cannondale has tackled the rear end of the bike with their Kingpin system. Before we look at that though, let’s look at this bike’s geometry and details.
Geometrically Speaking
Looking at the profile of the Topstone, it appears to be slightly longer and slacker than a traditional ‘cross or all-road bike. The size large I rode felt a little longer than I was used to in the size range. With a 39.4cm reach and a 57.9cm top tube, the Topstone Carbon felt comfortable without being too stretched out. The 5.8cm of trail puts the front wheel out a bit further too, reducing toe overlap on the smaller sizing and making the bike more off-road friendly, especially on the descents. All with a 415mm chainstay to get that rear wheel tucked in as close as possible.
The Devil is in the Details
Aside from the beautiful paint, which is mostly covered here by my half frame bag and a nice layer of dust, the Topstone Carbon has everything you’d want for a bike that is only limited by the amount of time you can take off from life’s responsibilities to ride. Want to do some dirt road bikepacking? The Topstone looks to be more than equipped to do so.
I feel more often than not, fenders and cargo attachment points are an afterthought, yet the Topstone Carbon addresses all these issues in very elegant and well thought out ways. For starters, there’s a special fender brake bridge that attaches under the seat stays via two bosses so you can attach a full fender, a drilled fork, a 3-boss cage mount on the top side of the downtube, a third bottle cage mount on the under, a bolt-on feed bag location on the top of the top tube, and it’s even set up to run a stealth dropper post.
For normal seat post users, the clean and hidden hardware offers a secure bite, while tucking the adjustment bolt up in the crotch of the seat tube cluster, away from view. The spec’d post has a nice flat profile at the top that also tends to flex a little bit also, further solidifying the soft rear end on the bike. Just be sure to use a torque wrench when clamping down!
One of the unexpected design features is the integration of Mavic’s quick-release/thru-axle hybrid, the SpeedRelease. You simply unthread the axle about a half an inch, pull it out slightly and remove it straight down via these notches in the dropouts and axle. It’s really neat and makes it easier to pull the wheels off for vehicle storage or roadside flat fixes.
Build Spec
You can’t go wrong with Ultegra RX, with its clutch derailleur and smooth shifting. The gearing on the topstone is perfect too, with a 46/30t front crank and 11-34t rear cassette on an 11-speed freehub. Even on our killer steep dirt roads, I never felt like I needed more gear inches. The price spec I reviewed comes with HollowGram 22 Carbon rims which are 22mm deep, 25mm wide (interior width), and are tubeless-ready. For its $4,200 price tag, Cannondale sets you up nicely on a bike that features a no-nonsense, reliable groupset and component list.
For the tech-friendly, the front wheel even includes a Cannondale Wheel Sensor, to help you keep track of ride data via their Bluetooth app.
The bars have a nice subtle flare to them, allowing for a wider grip when descending, although the cockpit is made from aluminum, which tends to deliver a stiffer ride than I’m used to with the Topstone’s big headtube area and bigger downtube.
Now, let’s get into that funky rear triangle…
Kingpin
Carbon frame manufacturers are always swimming upstream in an effort to make their oversized, stiff frames more compliant. Over the years, we’ve seen a variety of attempts to soften the ride quality of these bikes, especially those geared towards the off-road market. It’s one thing to make a crit bike super stiff for hour-long races, but what about all-day events like Dirty Kanza or Land Run 100? The roadie 2.0 market is a finicky crowd and getting them to let go of their stiff, easy to accelerate frames isn’t easy, so companies like Cannondale have worked to develop in-frame tech that alleviates carbon chatter on their off-road machines like the Topstone Carbon. Their answer, for the Topstone anyway, is Kingpin.
Designed around a collet-locking bolt, or LOCKR Pivot, the stays are mounted mid seat tube via an axle and allowed to pivot up and down, thanks to the flattened and flexy chainstays. It’s not a linkage per se, yet a feat of engineering within the carbon layup that lets the bike flex up to 30mm over rough terrain. Does it flex? You bet. Is it noticeable? Yep! The Kingpin at first feels as if your rear tire is a bit low on pressure – an ironic point that we’ll get to later – and definitely floats across rough terrain. It’s not the Kingpin itself that caused a bit of pause in this review period, it’s what was required to make it work efficiently that causes concern.
This technology is pushing against the downtube to overcome its stiffness. Visually, the bike is tied together by a hierarchy of tubing profiles. Ranking from largest to smallest width: the large downtube, flattened seat tube, top tube, rear triangle. It looks like a very stiff bike and arguably, the front end is very stiff thanks to the down tube. This larger downtube could be the direct result of the engineering occurring at the rear of the bike.
Wide and Dished
The bottom bracket measures 83mm and the seat stays butt right up against this edge beautifully. As someone who has worked to widen my pedal stance to alleviate knee pain, I found the Topstone’s wider pedal stance to be quite nice. So why the wider bottom bracket? Keep in mind, 83mm is a whole 10mm wider than ‘normal’ and these days, in the pursuit to make a carbon bike more comfortable during long rides, it seems like that’s a good place to start.
The bottom bracket isn’t the only thing that has been nudged a bit. In fact, the entire drivetrain is pushed outboard 6mm, including the dropouts, to allow for a bigger tire clearance with all this carbon wizardry taking place. Then, the cranks also require a special offset, similar to a boost ring in a boost MTB drivetrain, to make this work. Even after all of this, the Topstone Carbon tends to flex a little bit at the rear triangle when you accelerate out of the saddle, which I actually really liked.
In short, to clear a 37mm tire, a double crankset, and allow for those nice and flat chainstays, Cannondale had to shift the entire drive side by 6mm, widen the BB shell to 83mm, resulting in a 10mm wider q-factor, and completely re-dish of the rear wheel.
It seems like those are a lot of hoops to jump through to get 30mm of passive suspension on an all-road bike. When at the end of the day, a 700x45mm tire run at 25-30 PSI – or even a 650b/27.5″ wheel running a 47mm tire – would offer a lot more compliance without the hassle.
Riding Experience
Look, there is a lot going on with this bike but the last thing I want is to make it seem like all these hoops Cannondale dove through with the Topstone Carbon were in vain. The bike really does ride nicely. It climbs, descends, and corners like you’d expect from the brand. While it took me a bit to get used to a small-ish off-road tire, once I adjusted my riding style, it offered up a fun and interesting riding experience. I’d imagine for road-minded people, the Topstone Carbon would feel like a familiar ally while riding off-road.
One other small qualm is the noisy bottom bracket, which manifested itself in the form of a rotational click. You know the kind. Just when you settle in on a long climb, a click occurs at the same spot on the rotation, like an unwelcomed metronome. It did this right out of the box and nothing I did was able to fix the issue. Keep in mind, we’re in a very dry and dusty place and no water touched the bottom bracket.
Take-Away
In my opinion, too much emphasis has been put on designing lighter, stiffer, faster bikes over the years, so as brands try to convert their road racing genes to off-road racing machines, they end up overcomplicating things, rather than taking the simplest road possible to obtain a goal. A lot of companies have done this, not just Cannondale, either. I agree that stiffness has a place on traditional road racing machines, yet I don’t believe it’s as important on an all-road or gravel bike. In the Topstone’s case, it offers a solution to soften the rear of the bike, while leaving the front completely rigid, which is where I feel the most fatigue during long rides.
While many brands have tackled various options to soften the entire ride experience, I still feel they are missing the overarching point that part of delivering a compliant riding experience can be solved by higher volume, lower pressure tires. There are other issues at hand for sure. Yes, it is difficult to clear a 700x45mm tire and maintain a 2x crankset but it is not impossible, especially with carbon. Trek did it with the Checkpoint, even though you had to slide the dropout back a bit to fit a 45mm tire, which I’d gladly do with any bike. Even bikes like the Stigmata and Hakka offer bigger clearances without having to do anything special to ride on a plush, chubby tire. To conceptualize, engineer, design, and fabricate a design like Kingpin and LOCKR Pivot is no small feat, but in this case I really feel the ends do not justify the means.
The original Topstone Aluminum opened up the off-road experience to riders looking for that Cannondale panache and in an honest and straight forward way, it delivered exactly that. If we’re talking about evolution, the Topstone Carbon is an interesting permutation, with design and technology that works, but also introduces a lot of complexities as an unfortunate byproduct.
Check out more information on the Topstone Carbon at Cannondale and be sure to read our review of the aluminum Topstone if you haven’t.