Like this site? Help us to make it better.


Castelli Viva Thermo Skully



A simple product done very well

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.

What the scores mean

Good scores are more common than bad, because fortunately good products are more common than bad.

  • Exceptional
  • Excellent
  • Very Good
  • Good
  • Quite good
  • Average
  • Not so good
  • Poor
  • Bad
  • Appalling

Castelli, Italian manufacturer of high-end cycle apparel, has produced a simple yet effective skull cap in its Viva Thermo Skully.

It's a thin thermal layer designed to be worn under the helmet, and it performs its job brilliantly. At first glance I was concerned that it would be too thin to deal with the cold snaps the UK has had recently – but those concerns were unfounded.

> Find your nearest dealer here

> Buy this online here

With a fleece liner and a shower resistant layer on the outside, the Viva Thermo Skully is stretchy and fits comfortably around the head – and heads of all sizes too. The cut means there's no bunching or excess, which makes adjustment of your helmet to accommodate it unnecessary. Just pop it on and away you go with lots of comfort and warmth.

The seams are well constructed, and while not taped they are flat to avoid any annoying digging or chafing against your helmet. The edges are actually seamless around the base, which also adds to comfort too.

The skull cap washes very well – after a few uses the fleece lining has remained as soft as it was when new, and the colours stay vibrant. This is particularly good, considering the bright red nature of the sample I had on test. If that doesn't match your kit, though, you can get it in blue or yellow fluoro, as well as more neutral white and black with the Castelli branding around the base. (And pastel blue 'Donna' versions for women – because men's and women's head shapes are so different...)

> Check out our guide to the best cycling kit to keep you warm in winter here

As with many Castelli products, it's on the pricey side at £19, but to be honest it's a nice piece that will last multiple winters, and does a great job in wintry conditions – just as good as my merino wool alternative.


A simple product done very well

If you're thinking of buying this product using a cashback deal why not use the Top Cashback page and get some top cashback while helping to support your favourite independent cycling website test report

Make and model: Castelli Viva Thermo Skully

Size tested: Uni, Red

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?

Castelli says: "Sometimes simpler products are better, and nowhere is that more true than on this skully. Thin Thermoflex fabric is extremely warm yet provides excellent moisture management and easily fits under your helmet. The raw-cut edges eliminate bulk under the straps. This really is perfection, simplified."

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


- Thermoflex is warm, soft and stretchy

- Flat-lock stitching

- Raw-cut edge lies flat and doesn't bunch under helmet

- 32g weight

Rate the product for quality of construction:

Very well made, with flatlock stitching for smooth lines and design.

Rate the product for performance:

Kept me warm even in freezing conditions. Very, very good.

Rate the product for durability:

The fabric will stain if lots of dirt gets on the bright colours – but I do mean lots of dirt. Maybe not the cyclo-crossers among you.

Rate the product for fit:

Comfortable and form fitting.

Rate the product for sizing:
Rate the product for weight:
Rate the product for comfort:
Rate the product for value:

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

Very easily – choose dark colours if you get muddy though.

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

Very well – I can't complain.

Tell us what you particularly liked about the product

Form fitting and slim profile.

Tell us what you particularly disliked about the product

I'd have preferred it in black, but that's personal preference.

Did you enjoy using the product? Yes

Would you consider buying the product? Yes

Would you recommend the product to a friend? Yes

Overall rating: 8/10

About the tester

Age: 25  Height: 188cm  Weight: 83kg

I usually ride: Specialized Allez Sport  My best bike is:

I've been riding for: Under 5 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

Latest Comments