Castelli Free Aero Race 4.1 jersey review

Cycling Weekly Verdict

The Castelli Free Aero Race 4.1 jersey takes a racing-oriented design and tones it down, adding features for use by the more general rider, without losing its aero edge.

Reasons to buy
  • +

    Comfortable race-fit jersey

  • +

    Claimed aero advantages

  • +

    Nice features for more general riders, including reflectives and a fourth zipped pocket

  • +

Reasons to avoid
  • -


You can trust Cycling Weekly. Our team of experts put in hard miles testing cycling tech and will always share honest, unbiased advice to help you choose. Find out more about how we test.

Castelli’s cutting edge clothing meets the marginal gains demanded by Team Sky. But rather than retiring its Free Aero Race 4 jersey when it improved on it for the racers, Castelli has reimagined it for the everyday rider. It retains its aero fabrics and excellent moisture management, while being easier to live with for the amateur rider looking for the best. It’s one of our favourite jerseys and part of our exclusive Editor’s Choice selection for 2018.

The original Castelli Free Aero Race 4.0 jersey was once Castelli’s top-spec racing-fit jersey. But when the newer Aero Race 5.1 jersey supplanted it at the top of the tree, rather than stop making the 4.0, Castelli tweaked its features to increase its appeal for a broader spectrum of riders.

>>> 15 of the best summer jerseys


castelli free aero race 4

Rear of the Free Aero Race 4.1 includes plenty of carrying space and small reflective tabs

Castelli says that the Free Aero Race 4.1 jersey still uses aerodynamic fabrics and cut, with a claimed saving of 12 watts at 40kph against a standard race-fit jersey due to its dimpled fabric on the front and the shoulders. The under-arm fabric also gets the aero treatment and is very stretchy for a close fit.

>>> Are aerodynamic fabrics worth it?

Although close, there’s enough stretch in the Castelli Free Aero Race 4.1 jersey that it’s comfortable not just for the racing snake. The fabric is also airy enough to provide plenty of airflow on hotter days, without being see-through. You still get quite close-fitting raw-edged sleeve grippers made of a thin mesh material.

castelli free aero race 4

Castelli makes the Free Aero Race 4.1 of airy fabrics for hot weather rides

>>> Castelli Free Aero Race Kit Version bibshorts review

At the rear, there’s a zipped valuables pocket in the Free Aero Race 4.1 jersey with a reflective zip puller, as well as reflective areas on the two outer open pockets. At the neck, Castelli has sewn in a backing strip behind the front zip to make it more comfortable. All the logos are printed rather than sewn on, so as not to upset the aerodynamics or irritate the wearer’s skin.

castelli free aero race 4

Single layer mesh arm grippers are a quality touch

It all adds up to a very comfortable jersey for longer rides, not just for racing – perhaps the most comfortable we’ve tested. It’s available in sizes from small through to 3XL, so there’s plenty of size choice and the fit of the Free Aero Race 4.1 jersey is size-accurate for the general UK rider.

Thank you for reading 20 articles this month* Join now for unlimited access

Enjoy your first month for just £1 / $1 / €1

*Read 5 free articles per month without a subscription

Join now for unlimited access

Try first month for just £1 / $1 / €1

Paul Norman

Paul started writing for Cycling Weekly in 2015, covering cycling tech, new bikes and product testing. Since then, he’s reviewed hundreds of bikes and thousands of other pieces of cycling equipment for the magazine and the Cycling Weekly website.

He’s been cycling for a lot longer than that though and his travels by bike have taken him all around Europe and to California. He’s been riding gravel since before gravel bikes existed too, riding a cyclocross bike through the Chilterns and along the South Downs.