It’s perhaps easier to write a list of things that Simon Smart does not know about optimising rider and bicycle for aerodynamics than the things he does.
In a few short years since moving from Formula One, the aptly-named Smart has become cycling’s go-to aerodynamicist.
The wheel rims he designed for ENVE Composites are regarded by many as the best in the business (not least by MTN-Qhubeka, who rode them to stage victories this year at the Tour and the Vuelta), but his attention has turned more recently to clothing, specifically to skin suits.
Smart was instrumental in the development with Endura of the skinsuit in which Alex Dowsett set a new Hour Record in May. It’s a long hop from carbon to lycra, but Smart is convinced that development of clothing offers the greatest bang for buck, in aerodynamic terms.
“I don’t think there’s much doubt about that. The main reason is that 80 per cent of the drag is coming from the body. It’s a bluff body, with a large amount of separation on the back of it, with a big wake and low pressure behind you. There’s big potential for improving the drag if we reduce that.”
Smart describes a “maturity” in the market for aerodynamically optimised frames and wheels. They are the “low lying fruit”, he says, and as such have been picked early. But there is still significant scope to improve the performance of clothing.
Fabric, however, while quicker to prototype than carbon - in just two days, Dowsett wind tunnel tested 14 iterations of the speedsuit in which he would go on to break the Hour Record - it can be a more complex material to work with.
“The surface texture - the fabric - is very sensitive, and also seam position: seams can be your best friend, and they can be a nightmare too. Of all the things I’ve worked on, for sure this is the most challenging, for many reasons.
“Body shape and fit changes between different people. When you think about an aerofoil section for a downtube, where we are playing with subtle details and seeing differences, it’s hardly surprising that when you're optimising a skinsuit around a subject that’s moving and changing all the time that it’s a moving target.
“Then when you put it on someone else, it’s a completely different target. The frame and the wheels are fairly static. Skinsuits are a real challenge, but worth it, because that’s where the performance is coming from.”
Smart describes clothing technology almost as the inverse of bicycles. Clothing has separate challenges – breathability, longevity, fit – and, lacking the more static mechanical parameters of a bicycle, rarely offers a point at which the engineer can declare a project finished. “In some ways, fabric is quite ‘alive’ compared to most things mechanical engineers are used to.”
Smart did not lack for willing accomplices in the development of a skinsuit fast enough to set an Hour Record. Dowsett is an intriguing mix of the metronomic and inspired, and Endura is one of the few large-scale cycle clothing manufacturers with in-house production.
Founder Jim McFarlane says that Endura made 57 prototypes of Dowsett’s skinsuit at its headquarters in Livingston; home to, among other things, the custom clothing division where the Movistar team kit is produced.
“We don’t have massive manufacturing, but we have every technology: whether that’s bonding, or ceramic blade cutting, or digital printing, and every type of stitching. It gives us far more flexibility to design different combinations and design concepts.”
In Dowsett, Smart had another willing accomplice. The rider describes the physical demands placed upon him by such a relentless testing schedule in unflinching terms.
“The day we tested 14 suits, I had the option of doing it over two days, but that would have knocked three days out of training. I said I’d rather just grin and bear it. By suits 11 and 12, I was getting blood on my chamois. It wasn’t easy, but once I’d got it done, it was back to training the next day.”
Reason suggests that working with a world class athlete like Dowsett must make Smart’s job easier, but while he is quick to praise a rider with British and Commonwealth time-trial titles and a Grand Tour stage win on his palmarès, he does not dismiss the amateur out of hand.
Any rider who is scientifically minded can improve his position on the bike with wind tunnel testing, Smart believes, but one without the necessary concentration and mental commitment to holding a position for up to two hours, will not.
Similarly, the “450w powerhouse”, gifted by nature with a huge diaphragm and rib cage, is less likely to achieve a radical change of position than the amateur limited to 300w. And the salaried rider cannot afford a period of adjustment where he might lost 30w from his FTP, while he learns to ride in the new position. “Everything’s fair in a way,” Smart concludes.
“It’s not just about the drag co-efficient. It’s about [total] efficiency. It’s trying to find the sweet spot in terms of position versus power delivery. That’s the definition of being a world class time-trialist: someone who can produce a good level of power with a good level of drag reduction. It’s that ratio that makes you win - nothing else. It’s not just being completely slippery, or having a massive amount of power. It’s the sweet spot.”
His work with Endura continues. The Scottish brand has a contract with Movistar until the end of 2016 and is pushing boundaries in the development of garments for Quintana, Valverde, Mallori et al. Smart’s work will inform the new developments in team kit.
“It’s been really fun working with Endura. I never, ever thought I’d get involved with clothing design in my life,” Smart chuckles.
“After something that’s engineering driven, you almost start to develop a look and a style, rather than it be derived solely from fashion. It’s kind of a challenge really. You can make things look good, and have a purpose to them.”