Castelli Gabba WS Rain Jersey

This new jersey from Castelli really is something different. The Gabba is made from a windproof and water resistant fabric that's breathable enough that you stay comfortably sweat-free when you step up the intensity.

The idea for the Gabba came from Cervélo Test Team (as was) rider Gabriel Rasch a couple of years ago - hence the name. The objective was to produce a stretchy, close-fitting rain jersey that could be used with Castelli's Nanoflex arm warmers. These are water resistant so the designers didn't need to go with long sleeves on the Gabba.

Why not just wear a standard waterproof jacket? If you're a racer, the main reason is that waterproof jackets flap, they don't sit flat, and that affects your aerodynamics. Plus, putting a jacket on and taking it off can be awkward, and wearing one will always affect your body temperature to some extent.

The Gabba is made from a new water resistant fabric that Castelli have specially developed with Gore. Windstopper X-Lite Plus is a 4-way stretch material - stretchy enough for you to get a good, close fit without any tightness. It's a little like other softshell fabrics I've tried, but lighter. It rustles more than a typical jersey fabric when you move -a bit like windproof panels on tights can - but it feels pretty similar to normal once you have it on. Wear a base layer underneath and it feels just like any other jersey.

The cut is similar to that of Castelli's Aero Race Jersey - a close, race fit - with a high collar and a flap to keep wheel spray off your butt. You could fold that flap up inside the hem when it's not needed but I found that it sat neatly with no flapping anyway so there was no need. There's quite a bit of reflective material at the rear to get you seen when the light isn't so good and you get three normal pockets in the lower back. Well, normal but for the eyelet in the bottom of each one to let water drain out.

In use, the Gabba is warmer than a standard jersey because it's windproof - there's no cool air getting through the fabric. That means you have to choose your other clothing accordingly to keep your body at a comfortable temperature. You can always open up the full-length YKK zip if you really need to, although that will affect the aerodynamics.

Even when you do get warm, the fabric allows a whole lot of vapour to escape so you don't immediately get uncomfortably sweaty. The Windstopper fabric isn't as breathable as normal polyester, of course, but you'll be surprised at just how well it can cope when you crank up your effort. You wouldn't want to be wearing this jersey in the height of summer or you really would melt, but Castelli give it a temperature range of 10-18C and that seems about right to me.

The Gabba proves its worth when the rain comes down. It's not completely waterproof but it'll keep you dry in a shower, the rain just beading up and rolling away. If you're caught in a prolonged downpour you might be better off in a full waterproof.

In that sense the Gabba is a bit of a compromise garment. On the plus side, you get a windproof jersey with a high level of water resistance, decent breathability, and the convenience of not needing to get a jacket on and off as conditions change. On the downside, it's not as breathable as a normal jersey and it doesn't keep the rain out as well as a waterproof jacket.

Whether it's the right choice for you depends on the riding you do. The Gabba is at its best for racing in changeable conditions - and I'd include cyclo-cross in there and sportives too if you're the sort of rider who goes all-out for the fastest time you can get.

Verdict

Windproof and highly water-resistant jersey for performance riders looking for an advantage in changeable conditions