Next level jersey.
The Castelli Alpha ROS Jersey is more than meets the eye, and it strives to be your go-to winter jersey this season. It's a hybrid between a jacket and a jersey and, like most of Castelli's clothes, it has a slim, next-to-body fit. What makes this jersey really unique is the double layer front for maximum temperature regulation with each piece having its own zipper. The Windstopper material and seam-sealing echoes the design ethos of the Alpha ROS jacket, but is suited for temps that are a little higher.
ROS stands for Rain or Shine, and Castelli uses that acronym on their premium products offering protection in cooler weather, both wet and dry. The ROS pieces are designed to perform better in the wet and wind than your typical thermal piece and give you more warmth and breathability than a rain cape. If it's a deluge of heavy, prolonged rain, you might want something a little more impermeable, but the ROS is designed to excel in the damp, drizzly conditions that we so often see in spring and fall.
The Alpha part of the jersey's title may be more familiar to long-time Castelli fans. It indicates the presence of the two separate layers mentioned above: thermal and weather-resistant. Since both layers feature separate zippers, it's possible to either batten down all the hatches in the face of a frigid, blowing drizzle, keep just the thermal layer zipped to boost breathability without sacrificing warmth, or let both layers flap in the breeze during intense efforts or climbing intervals.
The Alpha ROS Jersey improves on last year's jersey with all new fabrics, which greatly increase its water repellent properties, and a reduction in seams, enhancing its resistance to rain. We also see new waterproof zippers, laser cut drain holes on the rear pockets, and a raw edge waist. The Nano Flex Xtra Dry back offers the most significant non-membrane water protection available and exceptional breathing. It might not keep every drop of rain out but it will leave you as comfortable, warm, and as dry as possible in more situations than any other garment.
- A race-cut, weather-resistant cycling jersey/jacket hybrid
- GORE Windstopper 150 is breathable, all-weather protection
- Racing fit is cut to eliminate flapping material
- 2 layer front design dumps heat during hard efforts
- Laser-cut mesh drains in the three rear pockets
- Reflective accents adds visibility in inclement conditions
- Castelli redefines all-weather racing kit
- Q & A
- Familiarity: I've used it several times
- Fit: Runs small
- Size Bought: XL
Performs as advertised. It's Italian made so be sure to account for that in the sizing. So if you're an XL order a XXL. Wore it on a cool, foggy, misty morning ride and was comfortable and dry the entire ride. Very happy with this and the price.
Great for Spring/Fall
- Fit: Runs small
- Size Bought: XXL
I've worn this a few times since purchasing. Temperatures have ranged from 30-55 degrees and it has performed well, with varying types of base layers. I would imagine you could go lower with the appropriate base layers. On the 30 degree day, I paired with a Pearl Izumi transfer long-sleeve base layer and was fine. When it got to 55, I simply wore a SS Castelli base layer. In both instances, I was sweating at times, but, stayed warm enough on descents.
I also have the Alpha Ros Jacket, which is almost the same design (internal vest, etc.). The jersey is a good complement to the jacket when it gets a little bit warmer. I am usually a Large in most street clothes, but, the XXL is the perfect fit. Snug, but, enough room for a base layer or two, if needed.
- Familiarity: I've put it through the wringer
- Fit: True to size
I've worn this jersey in temps from 40-55, I'm sure you could go a little more or less but thats what I've used it for. I've used it with a base layer and without. Fit is really nice, I like the Castelli cut, no flapping around at speed on the road. I put as true to size, but true to size as far as Castelli goes. Castelli is more of a euro fit. It's a little more generous than a Castelli short sleeve jersey as it leaves just a little room for layering. Highly recommended piece for spring and fall. I am 5'7. More than happy to answer any questions, feel free to contact me directly email@example.com
Warm even in pretty cold weather
- Familiarity: I've used it once or twice and have initial impressions
I wore this today with the outside temperature at 35 degrees. I did not wear a base layer and it was great. The wind stopping technology was amazing. Once I got up to warmth I was very comfortable. Once again with any Castelli go up a size if your American.
I have last season's Alpha FZ wind jersey. On that piece, the internal lining only covers the front torso and back torso while the sides, shoulders and arms are plain un-insulated windstopper fabric (much like a "perfetto" piece). It's still a great jersey but this omission just means it's not quite as warm as it could be. Does this new ROS jersey have insulation down the sides, shoulders and arms or is it much the same as the older Alpha FZ?
From what I can see, it's just the vest area. Torso only; no arms. With tops like this, I always prefer flexibility, anyway, so I opt for the shell and baselayer approach. And frankly, at this pricepoint, I think the eVent membranes on Giordana's AV gear are better options. They breathe far better because they don't require the presence of moisture before they start breathing. (This is coming from someone whose winter cycling setup is a merino base layer and a Gabba jersey. The eVent membrane on Giordana's AV stuff is just better.)
- Familiarity: I've used it several times
My first test has taken this on a brisk 48 degree day. I climbed up Big Cottonwood Canyon gaining about 2000ft elevation gain before plummeting back down. The Windstopper did what it is supposed to do. Stop the wind. I think this jersey will have a range of appropriate temperatures depending on baselayer used. I could see that being in the 40-55 range most comfortably. I really liked the cuffs on the sleeves- perfect for tucking in or putting over gloves- depending on which gloves you have.
My favorite feature was the built in ‘vest/inner liner’- This was perfect as the climb up I was heating up quick and opened the outer layer up. Zipped it back up at the turnaround and let the Windstopper do its thing on the descent. 5’11 175lbs the large fits great.