Giro Chrono Base Layer review – winter luxury, at a price

The Chrono is an easy base layer to reach for – warm but not too warm, and superbly soft and stretchy

A man in a base layer by a tree
(Image: © Sean Fishpool)

Bike Perfect Verdict

With really good wicking and just enough loft to have a noticeable thermal benefit, the Chrono Base Layer is all about dry warmth and comfort… though it’s not cheap.


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    Snug, well-articulated fit

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    Super-soft and comfortable


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    Premium price

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Giro’s Chrono base is a nice reminder that no matter how performant a piece of kit might be, it’s not going to get a look in unless you want to use it in the first place. So a winter base layer might be impressively warm and dry, but if it’s a bit loose or tight, or short or funny looking, most days it’s not going to leap out of the kit drawer unless I *really* need that performance or everything else is in the wash.

I’m going to sound like a bit of a fanboy here but the Chrono Base is so soft and stretchy and decent looking that you're glad to wear it any time. And it backs up its comfort from the cupboard with good unobtrusive performance out on the winter trail. It’s a deserved best buy in our guide to the best winter base layers.

Short sleeved cycling base layer

Stretch panels and diagonal shoulder seams make movement easy (Image credit: Sean Fishpool)

Design and specifications

The Chrono Base has a very lightly brushed inner face, to trap a little warm air and increase the surface area that can draw sweat off the skin. Its fabric is made from 60 per cent nylon (light and soft and decent at wicking), 30 per cent polypropylene (which can be very good at wicking, durable  and very non absorbent, but a bit rough by itself), and 10 per cent elastane for stretch.

The fabric has different textures in different places; lightly ribbed in the back, the top of the sides and under arms for articulation; and patterned with slightly more breathable pinholes on the front and where you tuck it in. The main body is seamless, and the shoulder seams are flatlocked and cut diagonally, again to help with fit and articulation.

At 102g, it’s actually one of the lighter winter bases on test, belying its cosy feel.

Short sleeved cycling base layer

Tiny perforations help breathability (Image credit: Sean Fishpool)


I wore the Chrono base  in temperatures from mid teens (centigrade) with a thin loose jersey on top, through high single digits with a slightly thicker layer or light jacket and arm warmers, to low single digits as part of a heftier layering system. In other words, for what you’d see from September through April. It was light and breathable enough that it released excess heat if you had a zipped layer on top. But cosy enough that it felt like a good starting point even towards freezing.

Sometimes soft or brushed fabrics can hold on to moisture and end up clammy, but the Chrono base did a great job of staying dry; it didn’t feel like a compromise at all.   

In terms of fit, at 5ft8 with a 36in chest I was at the upper end of the XS/S size (33-37in) and it fitted perfectly for body length and articulation around the shoulders. I’m a big fan of the diagonal ‘raglan’ shoulder seam cut; you end up with a really smooth close fit over the top of the shoulder and down the arm, and under the arm too, and I liked the longish cut of the sleeves. The super stretchiness meant it was 100 per cent in contact with the skin across the body, which really helps wicking and for heat retention, though if you’re much bigger you’d want to go up a size; I would have found the fit a bit too noticeable when breathing if it was any more snug.

Short sleeved cycling base layer

The fit is close throughout, but not restrictive: base layer gold (Image credit: Sean Fishpool)


The Chrono Base is priced at the luxury end of things (or the Christmas present end of things), but chances are it would see a lot of use if you had one. It works nicely through autumn, winter and spring, and it’s an easy base to reach for. Like any flat-woven top, it won’t dump heat as fast as an old-school string-mesh base, but that’s the only criticism I have.

Tech specs: Giro Chrono Short-Sleeve Base Layer

  • Price:  $70.00 / £49.99 / €60.00
  • Colors: Men’s:  Black, White; Women’s: Charcoal
  • Weight: 102g (XS/S)
  • Sizes: Men’s XS/S (tested); M/L, XL/2XL; Women’s 2XS/XS, S/M, XL/2XL
  • Materials: 60% nylon, 30% polypropylene, 10% elastane
Sean Fishpool
Freelance writer

Sean has old school cycle touring in his blood, with a coast to coast USA ride and a number of month-long European tours in his very relaxed palmares. Also an enthusiastic midpack club cyclocross and XC racer, he loves his role as a junior cycle coach on the Kent/Sussex borders, and likes to squeeze in a one-day unsupported 100-miler on the South Downs Way at least once a year. Triathlon and adventure racing fit into his meandering cycling past, as does clattering around the Peak District on a rigid Stumpjumper back in the day.

Height: 173cm

Weight: 65kg

Rides: Specialized Chisel Comp; Canyon Inflite CF SLX; Canyon Aeroad; Roberts custom road bike