Review: Introducing the New Giro Helios Spherical Helmet

Review: Introducing the New Giro Helios Spherical Helmet

Written by Contender Bicycles, on March 03, 2021

We're big fans of the Giro Aether road helmet. The inclusion of their Spherical technology made for a road helmet that was light, safe, and breathed exceptionally. If there was anything the Aether couldn't do, it was the price. Not so with the all-new Giro Helios helmet. With cutting-edge technology at a stronger price point, we think the Helios will be a sure-fire hit. Here's why.

Spherical? But I Already Have MIPS!

For those not in the know, MIPS is essentially a slip plane that lets the helmet slide around relative to the helmet. The slip plane is usually a conspicuous yellow piece of plastic that, while beneficial in reducing rotation forces to the brain, does a great job of getting caught in long hair and limiting breathability. Most every helmet we have here at the shop has MIPS in some form, and while many are better than they ever had been. The new Giro Manifest helmet, which offers the latest generation of what they call Spherical MIPS, is light and airy for a helmet that offers the coverage it does.

a man wearing the Giro Helios Spherical Helmet

Spherical, or MIPS Spherical is what lends the Helios helmet it's distinctive shape. As on the Aether and Manifest MTB helmet (review HERE), the helmet has two parts: a lower, stationary part, and a mobile, sliding piece above it that is tied together with some elastomers. The sound of the pieces moving past one another is the same (but without the squeaks!) as is the resistance between the two pieces. The difference here is that if you crash, you’ll catch the outside part first, rotating and deflecting the force your head might feel in other directions. Further, the pieces of foam are different densities to try and deflect forces accordingly to address both high and low-speed crashes.

Giro’s data claims that this is an excellent helmet in regards to force dissipation. Like anything else, we are typically skeptical about safety system claims without testing and data to accompany the claims. But their claims in regards to cooling, comfort, and overall performance are justifiable, and in most cases completely valid.

Giro Helios Spherical Helmet

More Ventilation, More Efficiency

One of the advantages of swapping the MIPS plastic slip plane for the Spherical's two independent pieces of foam is the potential for much greater ventilation. Helios loses the AURA arch ring of the Manifest or Aether, but it has much of the same air channeling and tunneling as the Aether and Manifest. There are 15 vents in total, which when paired to the internal channeling Giro has done on the inside of the helmet, will do a great job of keeping the sweat from pouring down.

Giro has included what they call their Ionic+™ anti-microbial to keep the helmet comfortable and catch some of your sweat as well. One thing we find to be particularly interesting is that they've included a bit more padding around the forehead than we've seen on any other helmet before, with the center front bit of padding actually coming down slightly below the helmet.

Giro Helios Spherical Helmet

It Fits!

We have always had a strong appreciation for Giro's helmets, but their inclusion of MIPS meant their helmets were "mushroomy" more often than not. The Aether did a great job of cutting down on the bulk, but the new Helios seems to do even better in that regard. We're happy to see the inclusion of Giro's Roc Loc 5 Air retention system, which allows riders to adjust how high or low the retention system sits on the back of your head.

Typical Giro helmets with MIPS have left those with rounder heads cold, but their Spherical helmets have generally fit a wider range of riders. We're happy to report that Helios falls right in line, though it never hurts to try on a helmet before you commit to it. Three sizes are available fitting heads diameters from 51cm all the way up to 63cm.

Giro has those concerned with matchy-matchy in mind too, with five colors to ensure you have a Helios that fits your range of apparel.

Giro Helios Spherical Helmet


The Giro Helios helmet is an impressive piece of kit. Spherical brings all of the safety benefits of MIPS to a helmet with none of the drawbacks, and the helmet itself is well-designed for road and gravel riding alike. And while $250 is still nothing to scoff at, we can think of few helmets that work as well for a wide range of riders as the Helios does.

Have any questions about the Giro Helios Spherical, or Giro helmets in general? Give us a call during business hours, or send us an email any time to


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