Casetlli claims that its Free Aero Race 4.1 jersey brings aero benefits to the general rider

Product Overview

Overall rating:

Score 9

Castelli Free Aero Race 4.1 jersey


  • Comfortable race-fit jersey
  • Claimed aero advantages
  • Nice features for more general riders, including reflectives and a fourth zipped pocket


  • None


Castelli Free Aero Race 4.1 jersey


Price as reviewed:


The Castelli Free Aero Race 4.1 jersey carries on a race-winning design, but modifies it into a more all-round garment

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.

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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.

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Castelli Free Aero Race 4.1

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

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.

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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.

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.


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.