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B'Twin Aerofit Windproof Long Sleeve Cycling Baselayer



An excellent winter baselayer – superb performance and value

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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Want a technical winter baselayer that will allow you to keep the other layers off? B'Twin's Aerofit Windproof Long Sleeve Cycling Baselayer could be the answer.

Baselayers – generally speaking – tend to be thin layers of fabric that help provide a passage for sweat to move from skin to the outside, and as a result perform a key function in keeping the body warm when needed, and cool when not.

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B'Twin's Aerofit is a technically constructed top with a race cut that's designed to do the former and help you resist the cold thanks primarily to its slightly thicker construction and front windproof panel. Putting it on is like donning body armour – genuinely making the cold outside seem a little less hostile compared with thin merino-blended baselayers and giving you the confidence to shed a layer when heading out.

BTwin Aerofit Windproof Long Sleeve Cycling Baselayer - back.jpg

Layering up is a key component of winter clothing for me, but a lot of the time I find myself feeling just a little too laid down; a little too heavy to be able to ride as comfortably and naturally as I'd like. Not so here – where normally I'd wear baselayer, normal jersey and jacket, with the Aerofit I only felt the need to wear it and either a thick jersey or jacket.

That seems like a small change, but what it does do is allow moisture to escape from your body more easily, through two layers rather than three. The Aerofit is also very adept at this, alongside its windproofness: moisture and excess heat is allowed to escape through carefully constructed seamless mesh panels on the rear and around the armpits, while the front does its job of insulating you from the cutting wind, in tandem with a nicely high neck.

BTwin Aerofit Windproof Long Sleeve Cycling Baselayer - chest.jpg

Make no mistake, this is a baselayer for temperatures in the mid to low single figures, and unless you genuinely struggle in cold temperatures, this plus a good quality long-sleeve winter jersey will do the job.

That's chiefly because the front black panel (called an 'Extrem Protect' layer) is a slightly softshell-like fabric, and functions as a physical barrier from the cold. Your torso is kept well insulated, and you barely notice the extra thickness when riding. Over three hours of riding, as B'Twin states, it performs as well as any winter baselayer I've tried – and not a merino fibre in sight!

BTwin Aerofit Windproof Long Sleeve Cycling Baselayer - detail.jpg

It's also long in the cut so can reach right down to your midriff no problem, especially if you size up, which you can do because the fit is so snug. There aren't any rubbing seams to speak of, and as baselayers work best when flush against the skin, this works in its favour. Throw in the fact that as long as you wash it with care (I went for a 40 degree delicate spin), it'll keep its shape, and soon become a go-to piece of clothing.

> Check out our guide to the best cycling baselayers

At the excellent price of £24.99 direct from the Decathlon website, this baselayer is a steal, and makes winter riding much more bearable if you really feel the cold.


An excellent winter baselayer – superb performance and value

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Make and model: B'Twin Aerofit Windproof Long Sleeve Cycling Baselayer

Size tested: Large

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?

Decathlon says: "This B'Twin Aerofit men's cycling base layer offers excellent perspiration wicking. The windproof membrane stops your body heat from escaping. Very stretchy fabric."

Tell us some more about the technical aspects of the product?


- Moisture management: The fabric absorbs perspiration to keep your skin dry.

- Warmth: Thermal barrier that keeps you from chills while cycling.

- Stretch: Seamless product with very elastic micro perforations. Slim fit.

- Windproof: Windproof membrane on the chest to stop you feeling cold when cycling.

Rate the product for quality of construction:

Looks and feels like a baselayer worth twice the price.

Rate the product for performance:

Performs that magic trick of keeping you warm without overheating or drowning you in sweat in testing conditions superbly.

Rate the product for durability:

No worries from my uses so far.

Rate the product for fit:

The snug fit will appeal to many – and so it should. A large works well for me, which is an indicator of the tight fit.

Rate the product for sizing:

Comes up slightly small, but isn't too much of an issue bearing in mind the cut and flexible fit.

Rate the product for weight:

Slightly beefy for a baselayer in general, but reassuring on a winter's day.

Rate the product for comfort:

It's a superbly comforting baselayer – ideal for tough winter days.

Rate the product for value:

£25 for a baselayer with this much ability in cold weather? Superb value, if you ask me.

How easy is the product to care for? How did it respond to being washed?

Very easy.

Tell us how the product performed overall when used for its designed purpose

Incredibly well – the best winter baselayer I've ever used, and I tend not to like long-sleeve garments.

Tell us what you particularly liked about the product

Fit, windproof panel on the front, ample venting on the back.

Tell us what you particularly disliked about the product


Did you enjoy using the product? Yes

Would you consider buying the product? Yes

Would you recommend the product to a friend? Yes

Use this box to explain your score

For a baselayer that didn't meet my usual first-glance wishes, it surprised me no end. Superb performance at an excellent price.

Overall rating: 9/10

About the tester

Age: 27  Height: 188cm  Weight: 80kg

I usually ride: Canyon Ultimate CF SL 9.0 SL (2016)  My best bike is:

I've been riding for: 5-10 years  I ride: Most days  I would class myself as: Experienced

I regularly do the following types of riding: time trialling, club rides, sportives, general fitness riding

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Cyclespeed Tours | 6 years ago

I have 3 of these, got 2 in a sale at about £15. 


Superb, I wear one every time I go out when it's cold. Makes the big name (and price) brands look a bit silly......

mostly | 6 years ago

I've been using the non windproof verison for the last 14 months or so, every bit as good as my craft l/s.

s_lim | 6 years ago

I have one of these, and a l/s and s/s version of the craft windproof baselayers, and haven't needed to wear a gilet or additional layers since. Out of those, the BTwin is the most versatile and comfortable to wear. Completely punches above its weight

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