Why the tyres at the Tour de France keep getting wider and the pressure lower

Daniel McMahon/Business InsiderTo go faster, Tour de France teams are opting for wider tyres and lower pressure.

DREUX, France – There’s no shortage of tech talk when the Tour de France rolls around, and it invariably has something to do with hyper-aero frames, ultralight wheels, nonround chainrings, slippery apparel, and even powdered chains. Teams will try just about anything to go faster. So it’s refreshing to see a more analogue innovation taking hold in the world’s preeminent bicycle race: wider tyres and lower tyre pressure.

As we wrote in a recent review of one Tour-worthy bike, there’s been a trend toward riding wider tyres with lower pressure, and for good reason: It’s essentially faster and more comfortable in non-lab, real-world conditions. That’s been backed by an increasing number of research studies, including a report by VeloNews. That flies in the face of conventional wisdom that said to go faster you needed narrower tyres with higher pressure. Think rock-hard, 22mm tubulars.

Vittoria Corsa tubular tyres TdF BMCDaniel McMahon/Business InsiderThe tyre width of choice for Greg Van Avermaet, the reigning Olympic champion and leader of the Tour de France for several stages, has been 26mm versus the traditional 23mm.

Last week at the Tour, Business Insider spoke with Geoff Brown, the head mechanic of the EF Education First-Drapac p/b Cannondale team. This is Brown’s 21st Tour, so he’s seen his share of trends. (He used to wrench for one Lance Armstrong.)

We asked Brown about the trend to embrace wider tyres and lower tyre pressure, something that once seemed counterintuitive in pro cycling but has become a standard of sorts among the very top teams.

“It depends on the road surface, but 10 years ago the standard was 23mm tyres at 8 or 8.5 bar, or 115, 120 psi,” Brown said. “And now it’s 25mm for regular road racing and 7 to 7.5 bar for front and rear, so a little less than 100 to 110 max on the bikes.” So what’s the deal?

Geoff Brown mechanic Tour de France cyclingDaniel McMahon/Business InsiderGeoff Brown, head mechanic of EF Education First–Drapac p/b Cannondale.

“There seems to be a lot more real science behind cycling now,” Brown explained. “A lower tyre pressure with more surface contact translates to lower rolling resistance, which is one of the main factors. And the bikes are much stiffer these days, with the carbon-fibre frames, especially the aero frames, and the aero rims – like when you’re running like a 50mm-section rim, which is quite deep – all that stuff is stiff, so the lower pressure helps provide more comfort for the rider.”

Vittoria Corsa Control tubular tyres 30Daniel McMahon/Business InsiderTaylor Phinney’s tyres for the Roubaix stage of the 2018 Tour ran a whopping 30mm wide — especially plump for the cobbled farm roads of northern France.

For what it’s worth, we didn’t see any 23mm tyres at the Tour this year – we did look at a lot of tyres – though of course we may have just missed them. By far the most common widths were 25mm and 26mm. And while it’s difficult to compare Tour speeds based on tyre width and pressure, the growing research and the massive push across teams to wider tyres and lower pressure speak volumes.

Could we see road tyres at the Tour as wide as 27mm or 28mm anytime soon?

“Things are moving along quite quickly here in our sport,” Brown said. “The disc-brake thing has gained real momentum, so on those frames you can certainly run wider tyres because there’s the clearance for it. I could see it evolving to 26mm or 27 mm as the standard road-racing tyre, sure. Why not.”

Even bigger riders – like the 6-foot-5, 187-pound Taylor Phinney – run tyre pressure as low as the lighter, more compact climbers, such as Rigoberto Urán.

“As far as pressure goes, they all stay the same because it’s still a team sport, and if Phinney is riding alongside Rigo and he gets a flat, he’ll need a new wheel quickly,” Brown said. “Everything is sort of centered around what the leader uses, so if the leader has 7 in his wheels, everyone has to have 7 in their wheels.”

Business Insider Emails & Alerts

Site highlights each day to your inbox.

Follow Business Insider Australia on Facebook, Twitter, LinkedIn, and Instagram.