The new Met Trenta 3K Carbon, which Tadej Pogačar used to win the 2025 Tour de France and Elisa Longo Borghini wore to victory into the Giro d’Italia Women, is 16% better ventilated than the previous version, according to the Italian brand’s data, while it performed 40% better in Virginia Tech’s impact tests – the world’s most recognised safety testing protocol – gaining a five-star rating and one of the best scores ever recorded. It features Met’s 3K Airframe, a carbon fibre wing structure that eliminates EPS from the internal frame, resulting in a continuous internal air channel, uninterrupted from the front intake to the rear exhaust, which ensures consistent airflow at both high and low speeds.
The original Trenta 3K Carbon was launched in 2017 to celebrate the Italian brand’s 30th anniversary and was the first helmet in the WorldTour to use carbon fibre, something which Met says allowed it to reduce the density of EPS foam without affecting the helmet’s capacity to absorb energy in an impact.
The new version follows the same principle and broadly the same aesthetic, but in order to post those improvements, it has been reengineered in Met’s new in-house wind tunnel called ‘the Tube’. When we visited Met’s HQ in Talamona, northern Italy, and were shown the wind tunnel in operation, senior engineer Matteo Tenni told us how the new helmet had been developed. “We used the previous Trenta 3K as the baseline and asked, what can we optimise here? That helmet had good ventilation, but now, with the Tube, we could push to the extreme level of making sure the airflow is entering each vent with a free path to the tail. The improvement is due in part to the increase in performance of the outlet. There is a direct relationship between the performance of the outlets, the temperature of the head and athletic performance.” Tenni is referring to the effect of overheating: in extreme temperatures – such as riders are now experiencing in Europe in mid-summer – the heart rate drifts upwards, putting a limit on the amount of power a rider can produce.
But how exactly can testing in a wind tunnel supply data about a helmet's ventilation? As well as the standard aerodynamic testing, Met can conduct thermal analysis with the Tube – or how effectively a helmet’s vents work. On a plinth inside the tunnel, a helmet is strapped to a cast aluminium headform – a dummy head – which contains 32 sensors. The headform is heated up to 38°C, the temperature of the human body under strain, and turned to face a wind that emulates racing speed. The sensors relay the exact temperatures at each point on the head as it cools down in the airflow. The helmet’s angle of attack and the wind speed can be adjusted to replicate a range of conditions and yaw angles, and this allows Met to check how each individual vent or channel works, or how quickly the whole head itself cools.
However, with aero equipment increasingly deployed even for mountain stages – Pogačar used the Colnago Y1Rs and the Met Manta aero helmet to win the Tour de France’s uphill time trial, for example – is there a possibility that riders will still choose the Met Manta aero helmet over the Trenta 3K even though the latter is better ventilated?
“The Trenta 3K is only slightly slower than the Manta,” says Tenni. “At the beginning of March in the Classics, the pro teams will use the Manta. In May, in early summer temperatures at the Giro, where there’s climbing, it’s a tough decision. But in the Tour de France in July at 40 degrees, legs will stay fresher with better ventilation – and the Trenta 3K is the most ventilated road helmet ever.”
As we saw with MAAP’s new Pro Aero jersey, as worn by Jayco-Alula and Liv-Alula, teams are now talking of cooling as the next marginal gain. “Even if it’s two or three watts, that’s still interesting for the pro riders,” says Tenni. “If you need ventilation, it’s our challenge to make it perform aerodynamically.” The new Trenta 3K’s aerodynamic performance is unchanged compared with the previous version, according to Met, but it crucially boasts that extra 16% in ventilation.
Met of course conducts impact testing at its facility in Talamona, but it also receives back helmets crashed by its pro teams for analysis. We were shown cracked helmets belonging to Brandon McNulty and Juan Sebastian Molano. “Everybody thinks that mountain biking is the real action sport but it’s road cycling,” explained marketing manager Achille Montanelli. “We sponsor a World Cup downhill team, world-level freeriders… but the kind of crashes that we get from the UAE team are incredible, and also the amount. We have a database of almost 150 helmets crashed in the last five seasons. Crashed with what we can define as high-energy impacts, not just scratches but cracks. We have statistics now.”
Tenni continues: “We can compare how the liner is cracking according to the position of the impact and we can understand how it can deform in the most efficient way, how we can control it and use it to develop future helmets.”
Montanelli: “At the same time, pro road teams want to have a very compact product, so sometimes we have to explain again that it’s a safety tool, so you can’t only ask for lightness, ventilation and aero. The studies around concussion, and also from the UCI’s point of view, things have changed completely. The teams are looking at the number of days riders lose from performance due to a concussion more and more. For them, maybe one month out of racing for a concussion means three months out due to the time it takes to get back to the level they can perform at. Riders have a two-year contract… as a rider they are always saying maybe I need to rest more, but they can’t. A broken arm is a broken arm, but something with your head is different, and I think riders and teams are starting to understand that a bit more.”
He concludes: “In this way we can give them more value. When they choose a helmet there is the money part, there’s the brand part, but also the expertise. You want a helmet that is aerodynamic, light but is also safe. Because keeping your rider protected means they are able to race even after a crash. It’s also something we explain to the rider and the team manager. It’s part of the package we can offer as a brand.”
The new Trenta 3K, with a visibly more reinforced section above and behind the ears than the previous version, has a claimed weight of 260g in the size M, 35g more than the outgoing Trenta 3K. For the 40 per cent improvement in impact testing, it seems like a small price to pay.
On the subject of price, the new helmet will retail at 400€ / £350 / US$450 / AU$580 – visit Met’s website for all the details, and read the full Met story in Rouleur 139.
MET Trenta 3K Carbon SPECIFICATIONS
• Weight M size: 260g
• Sizes: S (52-56cm) | M (56-58cm) | L (58-61cm)
• Certifications: CE | US | AS-NZ
• 3K Airframe: integrated carbon cage for enhanced performance
• Mips AIR®: ultralight rotational protection system
• Optimized fit: secure and comfortable internal shape
• In-mould polycarbonate shell with high-protection EPS liner
• Safe-T Orbital system: 360°, vertical and occipital adjustment
• Air Lite straps with adjustable divider
• 24 ventilation ports with internal air channeling
• Sunglasses ports integrated into side vents
• Minimal contact with the head for max ventilation
• Helmet soft bag included
