The new Cannnondale SuperSix Evo has just launched, and to improve upon an already nicely well-rounded frameset, the brand has introduced several novel design features that represent an uncommonly comprehensive update on the old design.

Be sure to check out our launch coverage of the new bike here as well as our first ride review (it turns out there’s a lot to say about it), but for an in-depth look into the new frameset’s design details, read on.

Thanks to a new tier of carbon composite, dubbed ‘Series 0’, Cannondale claims a weight of 770g for a painted size 56cm SuperSix Evo frame, meaning the Lab71 top-spec SuperSix Evo can achieve a complete build weight of 6.8kg.

Lab71 is the moniker now given to the top tier Cannondale bikes across all categories, and they’ll be available in limited numbers. Lab71/Series 0 now sits above the Hi-Mod tier, which was Cannondale’s previous pinnacle. I got to try a Hi-Mod-level bike, which uses a SRAM Red AXS groupset alongside the slightly lower grade frameset.

There is a claimed 40g weight increase from Series 0 to Hi-Mod (then a further 80g increase from Hi-Mod to Carbon tier), so with that, alongside the slightly heavier groupset (Red AXS is around 200g heavier than Dura-Ace R9200), I’d estimate the bike I got to ride to be around 7kg. That’s not bad for a second-tier bike, especially given the slight weight increase is really the only difference in performance.

Series 0 is apparently differentiated by the use of a special type of carbon fibre in the frameset composite blend that Cannondale is one of the first to use in the bike industry. The brand is tight-lipped over what it is exactly, but says the fibre’s properties allow it to create both torsional and lateral stiffness in the same material ply (where, more usually, two differently orientated plies would be required), therefore making the bike lighter for the same stiffness and/or shape.

This has let the brand extend certain tube dimensions without making the bike heavier. The seat tube and post are the best example of this – both areas are markedly deeper than on this bike’s predecessor. They’re narrower too, to the extent that a Shimano Di2 battery can no longer be stored in its usual place in the seatpost.

Balanced attributes

Brazo de Hierro Photography for Cannondale

Despite the deeper chord length of the upper seat tube and post, comfort is said to be the same as the previous bike.

‘With that deeper chord length, it is harder to create a lever on the seat tube and flex it for comfort,’ says Dr Nathan Barry, Cannondale’s aerodynamics expert. ‘So we had to influence the rear triangle in different ways to regain what the seat post shape lost. The drastically dropped seatstays direct force from rear wheel into seat tube which is bending like a leaf spring. The bend is facilitated by the profile of the tube near the bottom bracket junction, where it is super flat.

Cannondale

‘Aerodynamics don’t matter down there so it could be wide frontally, which maintains its second moment of area to preserve stiffness, but flat in profile to encourage flex.’

Cannondale

To accommodate the displaced Di2 battery, Cannondale has bonded a composite sleeve inside the bottom of the down tube. This uses a grommet to secure and protect the battery, and Cannondale specify a Di2 wire length to ensure the battery can’t slide out even if the grommet becomes dislodged.

Cannondale

Incidentally, there are an uncommon number of ports on SuperSix Evo’s down tube. Alongside the battery hole, there is the standard bottle cage mount, and below that a grommet covering an access hole for the wiring of Cannondale’s SmartSense system of lights to connect to a battery, which would have to be hung from the bottle cage mount.

At the top of the downtube there’s a cover near the head tube to house a junction box for previous generation Shimano Di2 or current Campagnolo electronic groupsets as well.

Boldly hidden cables

Brazo de Hierro Photography for Cannondale

Thankfully things are tidier at the front end – regardless of whether an electronic or mechanical groupset is used, cables are now fully integrated through the bars, stem and into the bike via a regular (as opposed to oversized, as it more common) upper headset bearing, courtesy of the SuperSix Evo’s wedge-shaped ‘Delta’ steerer.

The pizza slice-shaped tube opens space for cables to run into the bike either side of it. In the context of a normal, round steerer tube, it’s pretty extreme in design, but Cannondale says it’s ‘supremely comfortable’, ie confident in its structural integrity.

‘The steerer tube is still carbon, but its outer layer is made with a material called Innegra,’ says Cannondale’s road product manager, Sam Ebert. ‘This is an extremely abrasion resistant material, but we only really use it as precaution. We’ve done countless hours of testing that demonstrates the effect of brake hoses and shift cables rubbing against the steerer and our Delta design lends itself to smooth cable path that negates abrasion.’

Cannondale

Abrasion resistance is one challenge, but the reception to the extreme cross-section is another. New systems for integrating cables have led to failures and recalls in recent times, but Ebert is confident that the Delta shape can stand up to both sudden and prolonged stress.

‘We put the design through voluntary testing because we always surpass ISO standards and work to our own standards, which are industry leading,’ he says. ‘On top of that, we put the Delta steerer through through an elective Zedler test. During the process we broke 10 stems but the steerer never broke. The test is essentially a monstrous sudden impact followed by a huge subsequent fatigue cycle. That’s where competitors have had issues, life after an impact. We feel exuberantly confident there’ll be no such issue with our design.’

Time will tell, but you’d like to think (given the potentially drastic consequences of any sort of failure or recall) that the Delta shape will be one steerer innovation that should stand the test of time.

Don’t miss our first ride review of the new Cannondale SuperSix Evo