Cannondale System Six

Cannondale are late to the aero bike game. While many of their competitors are on to their second or third generation aero frames, the American company from Connecticut has been watching from the sidelines. Cannondale learned a lot about aero bikes before embarking on the design process for the SystemSix: they saw the mistakes made by other companies who prioritised aero gains over ride quality, handling, or maintainability and, rather than release their own aero bike with these weaknesses, they waited until they’d perfected the SystemSix.

In fact, the biggest compliment you can pay the SystemSix is that it doesn’t feel like an aero bike. The ride is as smooth as the SuperSix, a frame that incorporates Cannondale’s SAVE seatstays and tiny seatpost and which is renowned for its exceptionally smooth ride. The handling is balanced and precise and it doesn’t suffer from any of the vagueness which some aero bikes exhibit. The cable routing is well thought out and easy for a mechanic to work on—something not often considered when purchasing a bike, but often lamented when handed a whopping bill for a “simple” job because most of the bike had to be disassembled to replace a shift cable.

I’ve worked on a lot of bikes over a lot of years and I’m always drawn to those exhibiting attention to detail, especially around cable routing. If the minor details are correct, my experience shows, the major details will also be correct.  

By offering the SystemSix with only disc brakes Cannondale are taking a brave stance on the future of road bikes; in addition to better brake performance, however, the disc brakes allow aerodynamic features to be incorporated into the bike.

When you look closely at a bike you’ll frequently notice areas where the manufacturer cut corners to save a few dollars with the hope no one would notice. Often that’s with the thru-axles. Cannondale could have saved a handful of dollars by installing the heavy, ugly thru-axles found on many bikes in this price range, but instead they fitted the nicest ones they could find.

The thru-axles screw into double-threaded dropouts which use a clever engineering trick to halve the number of turns it takes to loosen or tighten the axles. The thru-axles themselves use Mavic’s Speed Release system which allows the wheels to be removed from the bike with the axles still inside them, and the combination of these two features ensures super-fast wheel changes.

The SystemSix features the modern standard for road bikes: a 100x12mm front and 142x12 rear dropouts. This is fantastic as it means the widest range of compatibility options with future wheelsets.

Not that you’ll be in a hurry to upgrade wheels. The Knot 64 wheels which come on the SystemSix range are one of the nicest original equipment wheelsets I’ve seen and were developed by Cannondale alongside the SystemSix frame. The Knot 64 wheels are, you guessed correctly, 64mm deep and look imposing on the aero frame. The bead-seat for the tyre is 21mm wide and has a unique shape which is 32mm at its widest point. Cannondale were not constrained by requiring a rim-brake track, and they licenced some aerodynamic technology from HED and developed the Knot wheels in conjunction with the frame for maximum aerodynamic performance. The rear hub internals are borrowed from DT Swiss’s excellent hubs, meaning easy maintenance and good availability of spare parts.

Crosswind performance for such a deep wheelset is remarkably good. The front wheel certainly gets pushed around by Wellington’s winds; it’s usually a gentle push, however, rather than a violent snap, which provides plenty of confidence when riding with deep wheels on windy days.

The wheels are tubeless-ready, opening up a wide range of tyres, and the Knot 64 arrived shod with Vittoria Rubino tyres and innertubes. The Rubino tyres are labelled as 23mm but widen out to 26mm on the rims; although I found them to be a little narrow for the coarse chip of our local roads, they rolled quickly and provided good cornering feedback and confidence. There is plenty of frame clearance for 28mm tyres if you’re that way inclined, however Cannondale do say that tyres measuring 25-26mm are aerodynamically best on the Knot 64 wheels.

The frame profiles of the SystemSix are clean and purposeful. The oversized downtube hugs the front fork below the headtube and shields the bottle cages from wind. The seat tube has a large cutout to hide the rear tyre from airflow. The seatpost is the same size and shape as the frame, which makes an elegant, purposeful blend as the two merge gracefully into each other. The twin-bolt seatpost makes it easy to correctly adjust the saddle position and it won’t slip or rotate if you whack a pothole. The binder bolt for the seatpost is neatly tucked away under the top tube; it is both out of sight and out of the airflow, but easily reached with a 4mm hex key.


An incredibly light titanium-railed Prologo saddle is perched on the seatpost. The saddle is another area where a bike company can save some money, but this seat is lightweight, good looking, and extremely comfortable. If you’ve ridden a Specialized Power or PRO Stealth saddle you’ll love the Prologo.

In keeping with the aero design is a pair of Vision carbon handlebars with flat aerodynamic tops, mounted to a matching Vision stem with hidden bolts. Viewed front-on, the svelte lines of the handlebars don’t offer much resistance to the wind, but the bar’s semi-compact curve gives many comfortable hand positions and match well to the shape of the DuraAce levers. The shift and brake cables run through the inside of the handlebars and exit at the back near the stem, which I found interfered with the spot my thumbs would normally be if riding on the tops of the bars. The handlebars have some integrated mounts for aerobars, which would make a great setup for a sprint-distance triathlete or a road cyclist who does the occasional time trial.

Cannondale invented the oversized 30mm crankset system found on nearly every high-end road bike. One of the key elements of an oversized bottom bracket is using a crankset designed to make the most of the extra available space to shed weight, and Cannondale’s Hollowgram crankset does exactly that. The CNC machined spindle and crank arms are incredibly stiff and they’re matched to a SpiderRing—a unique system where both of the chainrings are machined from a single hunk of aluminium to save additional weight and increase chainring stiffness. Stiff chainrings mean precise front derailleur shifts, something we all love.

The SystemSix is offered in New Zealand as either a high modulus frame-set or as a complete bike with DuraAce mechanical shifting and hydraulic brakes and the regular modulus frame. The DuraAce groupset on my test bike functioned as you’d expect it to: flawlessly. Cannondale’s work developing cable routing really helps here, as some other bikes in this aero category suffer poor shifting even when brand-new because of the tight bends and kinks required to run the cables between the shifters and derailleurs. The SystemSix cables exit the aero handlebars and enter the area in front of the headtube and are aerodynamically protected by a carbon shield. Once into the monocoque of the frame, the cables have foam liners to reduce cable rattle and a clever guide at the bottom bracket to keep everything organised. There is a carbon fibre cover on the downtube that can be replaced if an electronic Di2 junction box is to be fitted.

The headtube shield is the only compromise made by Cannondale’s engineers towards aerodynamics: In order to prevent the cables being crushed, the SystemSix handlebars can only be turned about 60 degrees before hitting an integrated fork-stop. This limitation makes itself known at slow speed and makes it impossible to track-stand waiting for a red light. Doing a U-turn on a narrow road can be tricky, but once you’ve accelerated to normal riding speeds there is nothing to worry about and the steering is unaffected.



I’ve owned quite a few Cannondale road bikes and I’ve always been drawn to them because of their excellent ride quality. I think the biggest compliment that you can pay a bike is not noticing it—to me the perfect bike simply disappears underneath me when I start pedalling. It may sound strange to spend all that money on a bike for it to be unnoticed, but if you’ve ever ridden a bike with either twitchy or reluctant steering you’ll understand my perspective. I’ve always found Cannondales to be perfectly balanced, and the SystemSix is no different. It steers easily and predictably with an almost mindreading ease whether you’re going fast or slow. Rider weight is positioned perfectly between the wheels to give confidence while cornering and the neutral front end tracks effortlessly.

Despite the large diameter frame tubes and oversized seatpost, the SystemSix is an incredibly smooth bike. Before riding it I expected the aero tube shapes and seatpost to provide a much harsher ride than my SuperSix, and I also expected the aero fork to be harsher than the svelte model fitted to the SuperSix. Thankfully neither of these assumptions was true: with a blindfold it would be impossible to tell the difference between the two bikes.


The SystemSix frame/fork/seatpost is about 300 grams heavier than the similarly sized SuperSix, so why would you choose the heavier bike? Cannondale say that despite the extra few grams the SystemSix is faster in almost every situation, even climbing. On climbs up to a 6% gradient the SystemSix’s improved aerodynamics and reduced coefficient of friction will hold you back less than the extra few grams, resulting in faster climbs. On the flats and going downhill the benefits are clear, with Cannondale claiming the SystemSix requires 50 watts less power to sustain 50 kph compared to a “traditional” lightweight bike, or up to 20 watts less power than the competition’s aero bikes. Anyone with a power meter knows how much training is required to boost your power by that kind of wattage. Sprinting paints an equally impressive difference, with the SystemSix being a full four bike lengths ahead of the SuperSix in a match sprint. Those are seriously impressive improvements on an already excellent bike.

With a price tag of $9,999 this Cannondale certainly isn’t cheap; but with its top tier DuraAce groupset, carbon wheels and carbon handlebars, the SystemSix offers good value and is competitive against other aero bikes in this category. This is one fast-looking bike and is certainly one of the best-looking and best-riding aero bikes on the market.


High modulus frame/fork/seatpost/headset: $4,999

Complete bike: $9,999

Words & Images: Tristan Thomas & Brent Backhouse

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