Castelli at the Grand Tours


Castelli has a rich heritage of creating revolutionary pieces of equipment which, over the years, have had a significant impact on the way cyclists dress. Thermal jerseys, aero jerseys and the celebrated Gabba are just some of the concepts that began with the brand and have been embraced by the masses.

Many of these products stemmed from the demands and feedback of pro cyclists, since Castelli has always had a close relationship with World Tour teams that trust the brand to provide the highest performance apparel.

Whilst most of the Castelli product range has been influenced by trickled down technology, there is a core range of products that is exactly the same as the kit used by the likes of Remco Evenepoel, Julian Alaphilippe and the rest of the Soudal Quick-Step team.

During Grand Tours like the Giro d’Italia and the upcoming Tour de France, this key range of race clothing will be at their disposal to maximise their performance and comfort on all 21 stages of the three week race, whether the riders are competing in a fast flat stage, a hilly stage or in the high mountains in the summer heat.

Below is an overview of the Castelli products you will see being used by Soudal Quick-Step during the Tour de France.

Free Aero RC Bib Shorts

For the last 15 years, the Free Aero Bib Shorts have been the ‘go to’ model for Castelli’s pro cyclists.

Designed to accompany an aero jersey, the Free Aero Bib Shorts have been aero optimised through extensive wind tunnel testing, without compromising their comfort.

After all, it doesn’t matter how fast a pair of bib shorts is if riders feel uncomfortable wearing them during long stages.

In 2022, Castelli launched the newest iteration of the Free Aero legacy: the Free Aero RC Bibs.

Made from only five panels, without using conventional leg grippers, these shorts are distinguished by a minimalist design that reduces friction spots, letting riders wear them in comfort, day after day.

To create bib shorts that do away with conventional leg grippers, Castelli went through 28 prototypes to find suitable materials with right level of compression. The industry leading Progetto X² Air Seamless seat pad, with its skin care layer designed to prevent sores, finishes them off.

Despite using what looks like relatively plain fabrics, compared with some of those used in the previous generation of Free Aero Bib Shorts, the RCs are also faster in the wind tunnel.

Aero Race 6.0 Jersey

Castelli was the first company to create an aero cycling jersey. Back in 2006, aerodynamics was widely considered to be unimportant for road racing – a sentiment that Castelli disproved through testing.

In fact, the gains made were so enormous that even the brand was astonished. The Split-Second jersey was born.

Fast forward to 2023, and Castelli is on its 6th generation of aero jersey. Countless hours have been spent in the wind tunnel, perfecting the fabric choices, fit and seam placement to create the brand’s fastest jersey to date, the Aero Race 6.0.

It’s a dedicated racing jersey for World Tour pros, and as a result, does fit very snugly on the athletic bodies of pros, without excess material to flap or wrinkle.

The jersey uses elbow length, raw cut sleeves made from Velocity Rev2 fabric, which is also used on the front. The back uses a 3D mesh fabric to help with moisture management during harder efforts, while three pockets mean riders can pack plenty of nourishment for a long stage.

The Aero Race 6.0 Jersey has been specifically optimised for speeds between 30-55kph.

For riders who like to wear bib shorts and a jersey, rather than a speed suit, this is the jersey they will likely grab from the wardrobe on competition days or when they’re in training.

Climber’s 3.0 SL Jersey

On hotter days, or during the mountain stages, it’s likely you will see riders in the Climber’s 3.0 SL Jersey. It was developed off the back of requests from GC riders, wanting a super lightweight jersey that would keep them cool while still delivering an aero advantage.

Racing up mountains is never easy, but in July, during the Tour de France, temperatures can be stifling, with minimal breeze for respite.

This jersey is designed to be as breathable as possible, making you feel almost like you’re not wearing anything, even while efficiently wicking excess sweat.

With the same cut as the Aero Race 6.0 Jersey, the Climber’s 3.0 SL also delivers an aero fit. However, instead of using aero optimised fabrics, it uses breathable fabrics, optimised to keep the rider cool and actively wick sweat away from the skin.

The Flusso 3D fabric on the front is highly perforated, to allow maximum airflow, whilst the back uses StradaPro 3D fabric.

These materials are very similar to those Castelli uses in some of its base layers, so there’s no need to wear one under this jersey on the hottest days.

As with the Aero Race 6.0 Jersey, the Climber’s Jersey uses a slight drop tail to make access to the pockets easier, whilst a YKK Vislon® zipper glides up and down smoothly, allowing simple on-the-fly adjustment.

Sanremo RC Speed Suit

Prior to 2011, skin suits were used only during Time Trials or by track cyclists. On the odd occasion road racers would use these suits, but they were pretty uncomfortable, not to mention impractical due to their lack of pockets or any way to take a ‘relief break’.

In 2011, Castelli released the first Sanremo Speed Suit: a one-piece skin suit, designed to be both aero and comfortable, with rear pockets and a revolutionary zip system, allowing riders to fully open the front to cool down or make that all important toilet stop during a long race.

For 2023, the Sanremo Speed Suit has been updated to feature the new Free Aero RC Bib Shorts in the lower portion. Up top, it still uses the Aero Race 6.0 Jersey, joined together with the shorts at the sides and back.

So, why would riders choose to wear this instead of the separate Aero Race 6.0 and Free Aero RC Bib Shorts? It’s a question of aerodynamics. Having the two garments joined together smooths the whole outfit and makes it faster.

Also, the removal of the bib straps reduces pressure over the shoulders, which some riders prefer.

If there is a stage where the team or riders must make efforts in the wind (whether while defending the GC or during a sprint stage), then the San Remo Speed Suit is likely to be selected for its combination of aerodynamics with comfort.

BTW Speed Suit

During the Castelli and Team Sky/Ineos Grenadiers partnership, the Classics specialists and domestiques requested a skin suit that would tip the scales more in favour of aerodynamics and away from comfort.

They wanted something more akin to a Time Trial suit, for maximum aerodynamic gains while sitting in the wind for long periods, whether on the front of the peloton or while going solo during Paris-Roubaix. The BTW was born.

Constructed from 4-way stretch fabrics, with a very tight and aerodynamic cut, it resembles the Body Paint TT suit more than it does the Sanremo Speed Suit. It’s smaller when not being worn and has a deep v-neck collar, to prevent irritation from the tight materials.

Designed using extensive CFD and wind tunnel testing, it uses a dimpled fabric on the sleeves and shoulder, which is slightly heavier compared to other fabrics but incredibly aero.

The BTW Speed Suit uses the recently launched Premio Black shorts, which are not only incredibly comfortable but also Castelli’s fastest in the wind tunnel.

The suit furthermore features just two pockets at the back, in keeping with its extreme aero shape, while doing away with the Sanremo opening. Relief breaks and general temperature regulation, therefore, are slightly more challenging while wearing it.

The BTW Speed Suit has been Remco Evenepoel’s outfit of choice for most races outside of the mountains. With his aggressive, attacking style, he needs the most aerodynamic skin suit in the peloton to give him marginal gains when he goes on one of his trademark, audacious solo attempts. The last two times that he’s won Liège-Bastogne-Liège, he’s done so wearing the BTW Speed Suit.

During the Tour De France, the sprinters and leadout train may well be spied using the BTW Speed Suit. Delivering a 3% aero drag saving between 45-65kph, it’s perfect for fast stages and sprint finishes, which is why it’s the outfit of choice for sprinter Fabio Jakobsen.