Cannondale SystemSix: Fastest Road Bike Ever?
Cannondale's latest fills the aero road gap in its line up, but just how fast is it?
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It’s launch season! As the cycling world enters the fever dream that is the Tour de France, manufacturers hope to take advantage of this collective madness to get eyeballs for their latest creations. We’ve already seen an innovative new MIPS helmet from Giro called the Aether that you can read about here, and today we get a new bike, the Cannondale SystemSix. This new bike adds the final missing piece to Cannondale’s lineup – Aero Road. We’ve seen EF Pro Cycling racing the bike already, but now we’ve got the details.
• PELOTON / Images Courtesy Cannondale
The Cannondale SystemSix
Looking very much like the SLICE Tri bike, the new Cannondale SystemSix was designed to be the fastest road bike ever made. Sure, that’s been just about every aero road bike’s claim, but Cannondale says that it has achieved it using a system approach. They claim it uses six unique elements: Frame, Fork, Seat post, Stem, Handlebar, Wheels – all working together. This is a bit of a puzzler since these elements are not unique and this is exactly how every bike works, but we digress.
More interestingly, the System Six has been designed not simply around aero goals. Cannondale began an exhaustive study of the six forces that resist your movement – Rolling Resistance, Wheel bearing friction, Drivetrain friction, Aero drag, Potential energy to climb and Kinetic energy to accelerate. Cannondale even has a huge equation that puts it all together. The goal was to build a bike that lowered all of these forces as much as possible, while focusing on those that would deliver the most benefit.
Much of the study centered on weight vs. aero and where the tipping point existed. The result was a six percent grade. When the road tips to six percent, aero and mass are both equal in resistive force. More number six! Below six percent, the aero is more important, above it’s weight. As such, both grams of drag and grams of mass were critical to lower. The frame itself is pretty light for an aero bike, 981 grams for a 56cm, up to 1085 grams for a 62cm and as low as 895 grams for a 47cm. Not earth shattering, but not bad.
It’s easy to see Cannondale, like most aero bike manufacturers, really looked to lower drag first, and they claim to have been very successful. In wind tunnel testing they claim to be faster than, well, everybody. They say it takes more watts to push the Trek Madone (a little under 10 watts) – more watts to push the Venge VIAS (a little over 10 watts), across a wide range of averaged wind angles. These are tests without a rider, and Cannondale admits tests without a rider are not real world, although they say tests with a rider show the same trends, but those numbers were not published. While these tests were completed at 30mph – not our average speed very often – even at 18mph the SystemSix will save you 17 watts verses a SuperSix. Noodling along at 18mph that’s around a 10% reduction in power. Huge, but similar to what other top aero road bikes will deliver.

These aero savings were achieved in the same way most modern aero bikes do it, truncated airfoils, deep carbon wheels and a one piece, integrated cockpit called the KNOT. We have yet to get our hands on a SystemSix, so have very few details on how easy to build or adjust fit the bike may be. A big piece of the puzzle here seems to be the new Cannondale KNOT64 wheels which Cannondale claims are faster than Zipp 454s and ENVE 4.5 across a wide range of averaged wind angles. Of course, they are a bit deeper than those wheels and heavier at 1642 grams a set, so it’s not really apples to apples.
Once we get a bike in for long term rest we’ll dig into the tech a lot more and get you ride feedback. Until then, here’s a few more details. The SystemSix is a disc brake only bike, the SystemSix Hi-Mod Dura-Ace Di2 bike costs $11,000, which includes the KNOT64 wheels and a Power2Max power meter on Hollowgram cranks. The entry level SystemSix Carbon Ultegra is $4000, but forgoes the power meter, the KNOT64 wheels and the KNOT integrated cockpit.
Is it the fastest road bike ever? That’s a tough claim to back up, as Cannondale is open about. They certainly believe so and it does seem undeniably fast, but in the modern world of cycling ‘fastest’ is a moving target and the bikes Cannondale tested against are sure to be outdated in a week or two. Stay tuned.


