World records are getting shattered in cycling at the Olympic velodrome. There are a few reasons why

Sam Welsford had just dismounted from his space-age bike, the one that costs about as much as a Range Rover, and looked at the record time his teammates from Australia had just set in the men's pursuit at the Paris Olympics.

“I reckon," Welsford said with a charmed smile, “we'll have to go faster for gold.”

That's because through the two days of track cycling at the Vélodrome National de Saint-Quentin-en-Yvelines, just a short ride west from the opulent Palace of Versailles, world records are getting shattered at a stunning pace.

The mark for the women's team sprint was broken five times Monday night before the British trio of Sophie Capewell, Emma Finucane and Katy Marchant dispatched of New Zealand in the finals. The Dutch men's sprint squad of Roy van den Berg, Harrie Lavreysen and Jeffrey Hoogland dropped their own world record twice on the way to gold the next night.

“The track is really fast and the temperatures are really high,” Hoogland said, “so we were hoping for it.”

Then there was Welsford and teammates Oliver Bleddyn, Conor Leahy and Kelland O'Brien. They not only beat the world record set by Italy in winning the gold medal in Tokyo, they obliterated it. Their time of 3 minutes, 40.730 seconds in their heat race was nearly two seconds faster, putting the Australians in the finals Wednesday night against their British rivals.

So what's with all the blistering times? It boils down to the perfect combination of track, technology and temperature.

What makes the Olympic velodrome so fast?

The home of the French cycling team, the velodrome just outside of Paris opened a decade ago with unique dimensions ripe for speed. It is 250 meters long, like most tracks, but it has a constant radius of 23 meters with 43-degree banking in the corners — and exceptionally smooth transitions between the straightaways and turns — that create a slingshot effect.

“The track shape really promotes fast team shooting, you know? Really long bends,” Welsford said.

Then there is the surface, made of specially procured Siberian pine, which was refreshed after the 2022 world championships.

The track requires meticulous maintenance. Each morning, the temperature and humidity inside the velodrome are checked to ensure they are at the optimal level. And before and after each race, the shims between the track surface and support beams are looked over to ensure that vibrations have not altered the track in any way.

“Two years ago it looked a bit shabby,” Belgium's Nicky Degrendele said, “but they've done a great job. The track is super fast.”

Why are the bikes so expensive?

There may be no Olympic sport where the arms race is more heated — and expensive — than track cycling, where the difference between winning the gold medal and missing the medals entirely is often measured in fractions of a second.

The most well-funded nations work closely with manufacturers for years on the latest concepts in lightweight materials and aerodynamic designs. Teams have experimented with moving the drivetrain to the left side, which can provide an edge when riders only ever turn left. They use the latest in carbon fiber and 3-D printing. And they often collaborate with companies from other industries, such as Lotus from the world of motorsports, as they seek to streamline their setups.

The UCI, which governs the sport, stipulates any equipment used in competition must be available for sale to the general public. But it won't come cheap. The bike Welsford and the Australians are riding from British manufacturer Factor carries a starting price tag of $60,000. The frame alone from Hope Technology that the British are aboard costs about $70,000, and you still have to buy wheels, handlebars, the saddle and the mechanical parts.

Even that pales in comparison to the V-IZU TCM2, though, which was crafted in collaboration with carbon manufacturer Toray for the Japanese team. It will set you back roughly $138,000 — but at least you get a full bike out of the deal.

How does the heat factor in?

It has been searingly hot inside the velodrome at the Paris Olympics, forcing uncomfortable spectators to use anything they can find to fan themselves. But those temperatures are ideal when track cyclists are trying to set quick times.

The reason is simple: warm air is less dense than cold air. So when a sprinter such as Hoogland from the Dutch team is pumping out 2,000 watts of power, he can move just a little bit quicker because there are fewer air molecules providing resistance.

“We're getting some good temperature in the track, really low pressure, and it supports those fast times," Welsford said, "and then with all of the equipment, the aero packages we have coming through, the times are just getting faster and faster.”