Giro’s newest product, the Aether MIPS, is a groundbreaking bit of road helmet technology that pushes boundaries in terms of safety, ventilation, fit and, for Giro, price. It’s being debuted by Team BMC riders in this year’s Tour de France and is available for pre-order now.

Giro loaned us a Matte Black/Blue Pearl model.

The Aether’s marquee upgrade over Giro’s current top-of-the-line helmet, Synthe MIPS, is the safety system Giro designed in-house, MIPS Spherical. Instead of the plastic slip liner found on all current MIPS helmets, the Aether uses two separate foam pieces joined by a series of elastomers that allow independent movement. Giro spent three years developing the Aether; it’s a safe bet the technology will eventually trickle down to other helmets in the Giro line.

(We interrupt for a quick answer to the question you may or may not be asking: “Aether” is pronounced “ether,” as in the upper atmosphere, or the anesthetic.)

We’re happy to say (and Giro, which loaned us this helmet, is probably happy to hear) that we didn’t test MIPS Spherical’s protective properties. Instead, three of us at Performance – product manager John Rogers, social media coordinator Abby Thiele and copywriter Mike Marino – took the measure of Aether for its fit and ventilation qualities, the latter of which Giro claims to be a major improvement over anything it has done before.

Read our introductory story for the Aether here.

John Rogers

“I like when a helmet feels like it disappears on my head and the Aether does; it just feels like it belongs.”

I’m always excited to review the latest offering from Giro, so when I first saw details about the Aether I couldn’t wait to get a sample in hand. My current go-to is the Giro Synthe MIPS, so using that helmet as a benchmark seemed like a great place to start.

The first impression before it ever went on my head was the excellent, crisp, clean lines and huge vents. Giro has been at the forefront developing more rounded shapes and the Aether follows this aesthetic. You can see the family resemblance to the Synthe.

When I flipped it over what I didn’t see was the MIPS liner and on closer inspection there was a “whoa!” moment when I noticed that Giro had designed two shells with a slip plane in between, called MIPS Spherical.

But let me back up for a second here and talk about the plastic MIPS liner we are all currently familiar with and, more to the point, some of its disadvantages. To be honest, I’m not sure I have personally experienced all of these. But some of the grumbles have been that the MIPS liner alters the fit of the helmet, can compromise air flow, snag your hair – little stuff, but issues just the same.

The Aether MIPS Spherical eliminates all these issues with lines as clean on the inside as the outside but still offering the safety features expected from MIPS.

John had several cyclists on the group ride ask him about the new Aether MIPS helmet.

Time for a test ride, and I was excited. I’ve always ridden a medium Giro and no exception here; the sizing was as expected and adjustment easy with the flat webbing and RocLoc 5+ Air fit system. I like when a helmet feels like it disappears on my head and the Aether does; it just feels like it belongs. Temperatures were brutal during my multiple test rides, never below 90 degrees and very humid – so yeah, it was hot. What I loved was that right off the bat I could feel air moving through the vents and over my head.

It’s light (269g for the medium I was wearing) and looks good. I had several cyclists ask me about it on my first group ride. The Aether stands out as something different in the sea of helmets.

I can’t speak to how effective MIPS Spherical is versus a standard MIPS liner, but I can tell you that I have visited Giro headquarters in Scotts Valley, Calif., talked with their designers and toured the extensive testing facility. I can confidently say there is no better equipped team in the industry.

To sum up, the Giro Aether is at the pinnacle in terms of safety technology, venting and aesthetics.

Abby Thiele

“With the Aether I felt cooler, more comfortable, and better protected.”

I test rode the Aether and then shot footage for about 4 hours in the North Carolina heat, and thanks to the large vents in the helmet I never felt uncomfortable or overheated. In fact, having to go back to my usual helmet the next day for a long road ride made me appreciate the Aether even more.

The Aether also looks attractive and stylish. When you think of a dual-layered, protective helmet, you imagine something large and mushroom-like. In fact, the Aether is streamlined and contours closely to the head so there is no bobblehead effect at all. You have this innovative protection while also looking sleek and trendy, which is what we all aim for.

Abby said the RocLoc 5+ Air retention system allowed for easier accommodation for her ponytail.

I also really like the added RocLoc 5+ Air adjustment system to the harness in the helmet. It allows for greater flexibility in the fit and eliminates annoying pressure points. It also accommodates my hairstyle and ponytail easily; I don’t have to wrangle to get it situated comfortably.

I currently ride a Giro Aeon, which does not have the MIPS system. My first thought was that the Aether would be bulkier or heavier because of the added protection. This was not the case, as the Aether felt much lighter, cooler, and more form fitting than my Aeon.

With its large vents, the Aether allowed much more air flow to pass through than my Aeon with its 24 smaller vents. Compared to the Aether, the Aeon is hot.

So, with the Aether versus the Aeon, I felt cooler, more comfortable, and better protected. I will definitely consider buying one for myself.

Mike Marino

“You can see that Giro sweated bullets on the details.”

You hear it.

The first on-the-bike thing I noticed about the Aether was the sound of the wind through the vents. Hit a certain speed and it’s there. A subtle whoosh. Just to make sure, I put my fingers in front of my ears to block the wind noise and I still heard it. I’ve worn many helmets and never heard that sound before. It’s not disconcerting or distracting, it’s just different.

The second thing I noticed was that after working up a good sweat (which takes me all of two minutes), I felt something as I was heading downhill at a good clip. Giro says the heat signature of the Aether and its 11 monstrous vents is 2 degrees cooler than the Synthe MIPS, and although I never tried the Synthe on a 90-degree day, I noticed something with Aether. It might have been my imagination, but it almost felt like a cold tickle on top of my head. The helmet I ride now has 37 vents and although it isn’t comparatively hot, the feeling isn’t there.

Going hand in hand with the sound I heard, it’s apparent that this Aether moves air.

(My current helmet also is 40 grams lighter than the Aether but the difference isn’t bothersome and, frankly, barely noticeable.)

Mike said the fit of the Aether was perfect, a first for him and Giro helmets.

Fit-wise, the Aether scores big. Full disclosure: Giro helmets never fit me quite well enough to buy one. The Synthe was close to being the first one I would have purchased (full disclosure 2: I didn’t) and the Aether fits much better … perfectly, to describe it simply. The RocLoc 5+ Air retention system is a definite improvement in that you feel it pull the helmet down on your head, snugly but not uncomfortably.

Even looking at the intricate logo – not a stick-on like the Synthe but actually cut out and, letter by letter, pushed through the shell – you can see that Giro sweated bullets on the details.


As for MIPS Spherical, none of us even noticed it. That’s good news for Giro and even better news for the pro riders who, in various levels of frustration, have torn out their slip liners from standard MIPS helmets.

Joaquim Rodriguez

(Example: One of the gripes was from now-retired professional Joaquim Rodriguez, who had solid bona fides: 47 wins and five grand tour podiums in a 17-year career that ended in 2016. According to Giro, Rodriguez was riding the new Synthe MIPS during the 2015 Tour de France and was being driven crazy because he said he could feel – and hear – drops of sweat dripping off the liner. Seriously.)

Finally, there’s the price: more than three Benjamins ($325, to be exact). That puts the Aether atop Giro’s road line (only the $550 Aerohead TT is more) and squarely in the not-for-everyone category occupied by bespoke frames, custom road shoes and most things Campagnolo. Not that there’s anything wrong with that. Giro knows there are plenty of entrants in the Wednesday Night Worlds who’ll be eager for this helmet because a) it’s radically different, b) it looks cool and is cool, c) it’s being worn in the Tour and d) it’s the new, best Giro ever.

If any of that is on your must-have checklist, congratulations. Your lid awaits.

(And if you have any questions about the Aether, leave your comments below and we’ll answer them.)


Giro’s Aether MIPS is now available for preorder from Performance Bicycle, with our initial shipment of styles and sizes available for delivery in late August. Order your Aether here today.



  1. I bought a Synthe before and returened it immediately. Even with Mips, these helmets don’t feel safe. I like POC Avip better, it has better head coverage including temple area. The straps are way comfortable than Giro Helmets. If these 2 issues are addressed by Giro, I will definitely buy Giro again.

    BTW, Poc still is lighter thatn Giro.

    1. Julius,

      The POC Octal (I think that’s the model you mean) sits lower on the head than most helmets; that’s one of its features. I haven’t tried it beyond putting it on my head briefly. AFA the Aether straps, I didn’t notice them at all. And the POC’s claimed weight is 244g vs. 250g (269g actual for our medium) for the Aether.

      Thanks for reading!


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