This new jersey from Castelli really is something different. The Gabba is made from a windproof and waterproof 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 waterproof 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 in that the seams aren't taped but rain won't get through the Windstopper fabric itself. It'll keep you dry in a shower, the rain just beading up and rolling away, but 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.
Windproof and highly water-resistant jersey for performance riders looking for an advantage in changeable conditions
road.cc test report
Make and model: Castelli Gabba WS Rain Jersey
Size tested: Large, black
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
It was initially designed for pro racers who wanted a more aerodynamic option than sticking a rain jacket on. It's suitable for road racers, cyclo-cross racers and anyone else looking for a performance edge.
Tell us some more about the technical aspects of the product?
The Windstopper X-Lite Plus fabric was designed especially for this jersey because there wasn't an existing fabric that was stretchy and breathable enough.
Castelli clothing is usually top notch in terms of construction.
The fabric is windproof, waterproof and very breathable and it builds into a jersey that does exactly what it claims.
Weight isn't a massive issue here either way, but if you wear the Gabba you won't need to carry a race cape in your back pocket.
It feels pretty much like a normal jersey if you wear it in the right temperatures and the breathability makes it more comfortable than wearing most rain jackets.
Hard to judge because there's no other jersey like this out there (although one is on the way from Gore). Considering that it does the job of a jersey and a waterproof and that the fabric has been developed especially, the price isn't too outlandish.
Tell us how the product performed overall when used for its designed purpose
It does exactly what it promises.
Tell us what you particularly liked about the product
The waterproof fabric.
Did you enjoy using the product? Yes
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
Anything further to say about the product in conclusion?
This is a product that all the other manufacturers will be trying to copy in the near future
About the tester
Age: 40 Height: 190cm Weight: 74kg
I usually ride: My best bike is:
I've been riding for: Over 20 years I ride: Most days I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, sportives, general fitness riding,
Mat has worked for loads of bike magazines over the past 20 years, and been editor of 220 Triathlon and Cycling Plus. He's been road.cc technical editor for seven years, testing bikes, fettling the latest kit, and trying out the most up-to-the-minute clothing. We send him off around the world to get all the news from launches and shows too. He has won his category in Ironman UK 70.3 and finished on the podium in both marathons he has run. Mat is a Cambridge graduate who did a post-grad in magazine journalism, and he is a past winner of the Cycling Media Award for Specialist Online Writer.