Castelli Alpha ROS 2 Light women's jacket review

Castelli's range of winter gear is becoming bewilderingly vast, but if you're looking for a 'suits most conditions' middle ground, this is the one to go for

Castelli Alpha ROS 2 Light women’s jacket
(Image credit: Michelle Arthurs Brennan)
Cycling Weekly Verdict

A few years ago, the Castelli Gabba (and the Perfetto which followed) was the go-to winter layer for riders seeking protection from the rain whilst still allowing for harder efforts. Since then, the range has expanded dramatically. The Alpha ROS 2 Light offers a more relaxed fit, and its double-layer construction means it is warmer. If you're after a middle-ground jacket you can wear in most conditions, this is an excellent choice.

Reasons to buy
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Reasons to avoid
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    Baggy sleeves

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Every year, Castelli sends the Cycling Weekly office a large box of new season winter kit to review. The size of the box seems to grow annually as the brand, whose scorpian logo is ever present on any British winter club run, allows its skews to multiply.

It's hard not to make any predictions, but with Castelli already making several entries over the years in to our hand picked choices of the best winter cycling jackets any delivery from the brand get's us pretty excited. 

Our box this year contained the heavyweight Castelli Alpha ROS, lightweight Castelli Beta ROS, and this: the Castelli Alpha ROS Light jacket. We're already into November, and so far I would suggest that if you're looking to get maximum wear from your investment, the Alpha ROS Light represents the best middle ground. The Gabbba and Perfetto are of course always going to be popular and are suited to harder efforts owing to the single layer construction.

Castelli Alpha ROS 2 Light women's jacket construction

The defining feature of the Alpha ROS 2 light jacket is its double layer make-up. On the inside, is an insulating ProSecco Strada lightweight fabric. Over the top,  and on the sleeves, there's an extra blanket of Gore-Tex Infinium Windstopper 150 material.

(Image credit: Michelle Arthurs Brennan)

The back of the jacket uses Nano Flex Xtra Dry material, with a focus on breathability and rain shedding thanks to a water-repellent finish. Each layer is fastened by its own independent YKK zip.

The wide lower hem was a real plus for me - the material here contains greater elasticity, creating a second-skin fit and ensuring the kit stays put when on the bike.

At the back, you'll find three rear pockets, with reflective details and laser cut drainage holes.

I've always felt drainage holes on pockets are a bit of a gimmick (have you ever found a pool in your pocket?) but then better to have than have not. There's an additional small zipped compartment at the hip.

The collar comes up high on the neck, and on this dark blue option, there's a little extra daylight visibility in the shape of a red strip.

Castelli Alpha ROS 2 light women's jacket: the ride

Pulling on the Alpha ROS light, the inner layer is soft and feels warm, whilst the outer rustles reassuringly belying its robust winter ready character.

The panel at the hem sits flush, in a race-fit style which makes it feel secure, whilst elsewhere the size small offered quite a bit more room than a summer Castelli garment might. It could be worth dropping down a size if you're on the border, but I liked this extra breathing room for zone two winter ambles.

(Image credit: Michelle Arthurs Brennan)

I did find the sleeves quite baggy, this is something I've noted of other Castelli women's winter garments. However, the excellent weather protection on offer means I still reach for this jacket every time it comes out the wash.

I've worn the Alpha ROS Light on cool but sunny rides - at around the threshold of 15ºc - as well as on winter mornings - and in all cases it has provided me with ample warmth without overheating. My only weather protection gripe would be that paired with a short-sleeved base layer, I found the inside of the sleeves got a bit sweaty which did cool me down.

The water resistance is perfectly capable of combatting light drizzle, though of course, it will let the outdoors in if you're caught in a proper downpour.

The £225 price tag makes this a considered purchase. However, I do still have a Castelli Alpah ROS jacket from last season that's going strong after heavy use. I'd happily wear this jacket in most conditions between October and March, layering it up for the really cold days, and I'd expect it to last several years - so I'd see it as an investment piece, and a wise one at that.

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Michelle Arthurs-Brennan

Michelle Arthurs-Brennan is a traditional journalist by trade, having begun her career working for a local newspaper, where highlights included interviewing a very irate Freddie Star (and an even more irate theatre owner), as well as 'the one about the stolen chickens'.

Previous to joining the Cycling Weekly team, Michelle was Editor at Total Women's Cycling. She joined CW as an 'SEO Analyst', but couldn't keep her nose out of journalism and in the spreadsheets, eventually taking on the role of Tech Editor before her latest appointment as Digital Editor. 

Michelle is a road racer who also enjoys track riding and the occasional time trial, though dabbles in off-road riding too (either on a mountain bike, or a 'gravel bike'). She is passionate about supporting grassroots women's racing and founded the women's road race team 1904rt.