Giro Helios Spherical review

Giro brings its latest MIPS protection to a premium helmet that's aimed at gravel and adventure riders as well as roadies

Giro Helios Spherical mips
(Image credit: Future)
Cycling Weekly Verdict

The Giro Helios Spherical is a superb lid that does it all and, like the more expensive Aether, integrates the latest safety tech without compromising comfort or weight.

Reasons to buy
  • +

    State-of-the-art MIPS

  • +


  • +


  • +


  • +

    Good looking

Reasons to avoid
  • -

    No eyewear dock

You can trust Cycling Weekly. Our team of experts put in hard miles testing cycling tech and will always share honest, unbiased advice to help you choose. Find out more about how we test.

The Giro Helios Spherical is the US brand's second road helmet to use Spherical MIPS protection, the first being the £269.99 Aether which we awarded a perfect score and which made our Editor’s Choice line-up in 2020.

The Helios has a lower price and an expanded remit: whereas the Aether was designed and styled purely for the road, the Helios is for “road cyclists, gravel enthusiasts and adventure riders.”

>>> Best road cycling helmets: buyer's guide

I’m giving the Helios another perfect score because in practical terms it does everything the Aether can do and even improves on it in some areas; it has a broader appeal, and it’s priced lower than the Aether.

Giro Helios Spherical: construction

‘Spherical’ refers to Giro’s exclusive MIPS-powered technology that it developed with the Swedish company in its own lab. Spherical tech does away with the clear (or sometimes yellow) plastic MIPS liner of the original helmets that sat directly against the head and got a bit sweaty, sometimes also pulling your hair. With Spherical, the sliding MIPS layer is integrated into the helmet itself: it's basically an EPS shell within an EPS shell. In this case, one is black and the other is green, and they can move independently of each other with 10-15mm of travel thanks to a low-friction layer sandwiched between them and secured with elastomer anchors.

So far, all three helmets with this system (the Aether plus the Giro Tyrant and Giro Manifest mtb helmets) have received a five-star rating from independent safety testers Virginia Tech.

Giro Helios Spherical

The idea of MIPS, whether Spherical or in its original format, is to add protection against rotational forces transferred to the brain in an angled impact.

The Helios is very slightly lighter than more expensive the Aether – 260g v 269g in medium – and according to Giro it also tested faster in the wind tunnel.

So why does it cost less? According to Giro, cooling is two per cent less efficient since the Aether has bigger (but fewer) channels – 11 compared to the Helios’s 15 – but for UK riding who’s going to notice that? And the Helios uses the Roc Loc 5 Air closure system rather than the Roc Loc 5+ Air and again, the difference is so minimal that you’ll probably struggle to tell the difference. I found the Helios fitted so well anyway that the closure system was a mere formality.

The ride

Spherical MIPS feels like a welcome return to wearing a normal helmet after the original plastic sheet-type MIPS system.

As for fit, it’s obviously best in non-pandemic times to try on helmets and find out which ones suit your head shape. I’ve read frequently that Giro helmets suit round heads better, but ever since my first Giro – the Pneumo of the early 2000s – I’ve found Giro helmets fit my more oval head very well and that includes the Helios. There are no pressure points front or rear and it doesn't move down the forehead in the cycling position when the neck is low but the head looks up. In fact it's the most 'invisible' feeling helmet I've worn for a good while – I couldn't ask for a more comfortable lid.

Giro Helios Spherical

Overall it has a lower-volume look than the Aether – it’s close over the ears with no mushrooming, and sits directly on the top of the head.

Since it was only launched at the end of last year I haven’t been able to test it in higher temperatures, but I can confirm that airflow is good.

The one thing it does seem to lack is an eyewear dock feature – I couldn’t get my sunnies to stick in any of the holes satisfactorily – but I’m not going to deduct a point for that.


The Helios priced lower than the Aether, but the Giro Synthe, which doesn’t use Spherical MIPS, is £209.99. The Met Trenta 3K is more expensive at £270, though the Trenta MIPS is priced at the same level; the Abus Airbreaker is also priced the same.

Any helmet over the £200 mark is firmly in the premium category, but here you’re paying for the Spherical MIPS tech, which is arguably the state of the art, in a supremely comfortable helmet that’s also lightweight, aerodynamic and good looking.

This is my new favourite helmet – and it's even in my club colours!

Thank you for reading 20 articles this month* Join now for unlimited access

Enjoy your first month for just £1 / $1 / €1

*Read 5 free articles per month without a subscription

Join now for unlimited access

Try first month for just £1 / $1 / €1