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The new Helios is the latest in Giro’s line of Spherical helmets. Debuting with the Aether, Giro’s Spherical helmets feature a slip plane claimed to reduce rotational forces on the brain in some impacts.
However, instead of the familiar MIPS plastic liner between the rider’s head and the helmet, Spherical helmets employ two nested shells: a “ball and socket” design almost literally two helmets in one, with the slip plane located between the shells. This design lets Giro use different foams in the shells for better impact protection, “The outer one is denser to help with high-speed impacts. The inner one is less firm to cushion the head in lower speed hits,” said Giro spokesperson Peter Nicholson.
Though it employs the same Spherical design, the Helios does not use the Aura polyamide reinforcing ring used by the Aether and Manifest. Without Aura, the Helios’s vents can’t be as large as the helmets with the reinforcement, which knocks ventilation down a peg.
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In Giro’s lab testing, the Helios’s cooling efficiency lags behind the Aether by two percent. My skull testing says different. Since late June, I’ve had a Helios, and to me, it feels like there’s a greater-than-two-percent difference. Air doesn’t rush through the Helios the way it does the Aether. The Helios is by no means hot or stuffy—it has internal channeling, and air moves through it well—but, compared to the Aether, ventilation feels only average. But then, I’ve yet to find a modern helmet with rotational impact protection that vents as well as the Aether.
Though it may not vent as well as the Aether, the Helios is a bit lighter. On my scale, a medium Helios weighed 260 grams while an Aether came in at 285 grams. Giro’s testing results also say the Helios is a bit more aerodynamic than the Aether, resulting from the Helios’s lower profile shape. Add the Helios’s $50 lower price point, and it stacks up well against Giro’s best road helmet.
The Helios’s design also sets it apart from the Aether. Aimed at the gravel/all road crowd, the Helios is a rounder, smoother looking helmet: One that doesn’t shout, “I RACE!” like the Aether. Coverage also drops slightly lower in the rear than the Aether’s, so the Helios covers more of the skull and provides additional protection if the rider falls backward.
Inside, the Helios’s padding gets antimicrobial treatment to prevent stink and bacteria buildup. The padding is soft, itch-free, and thin—the pads don’t get soggy with sweat, and they dry fast too. The webbing is thin, supple, and lies flat. Like the padding, the straps don’t absorb much water, so they never feel swampy against your skin. The strap splitters don’t have a mechanical lock, so they’re very low profile, but they can creep, necessitating occasional fiddling to slide them back to their proper position. Giro’s familiar Roc Loc system fine-tunes fit. This version is height adjustable and features a new, slightly larger dial that’s easier to adjust.
After four months of testing, my conclusion is the Helios is a light, comfortable, great fitting helmet that offers the benefits of the latest protection technologies. But, styling aside, Giro now has two very similar high-end road helmets. Though it is $50 less than the Aether, the Helios is still a very high-end helmet. If I were helmet shopping at these prices, I’d spend the extra $50 to get the Aether: a light, comfortable, great fitting helmet with class-leading ventilation.
Spherical is fantastic and helps Giro make some of the nicest helmets you can put on your head—they’re comfortable and offer enhanced protection against rotational forces on the brain. The Helios is a fine helmet but I’ll be more excited when Giro brings this technology into a $160 road helmet. That’s not asking too much: Spherical is in the $160 Tyrant mountain helmet. Where’s the road equivalent?
The Helios is in stores today. It comes in three sizes—small, medium, large—and five colors.
A gear editor for his entire career, Matt’s journey to becoming a leading cycling tech journalist started in 1995, and he’s been at it ever since; likely riding more cycling equipment than anyone on the planet along the way. Previous to his time with Bicycling, Matt worked in bike shops as a service manager, mechanic, and sales person. Based in Durango, Colorado, he enjoys riding and testing any and all kinds of bikes, so you’re just as likely to see him on a road bike dressed in Lycra at a Tuesday night worlds ride as you are to find him dressed in a full face helmet and pads riding a bike park on an enduro bike. He doesn’t race often, but he’s game for anything; having entered road races, criteriums, trials competitions, dual slalom, downhill races, enduros, stage races, short track, time trials, and gran fondos. Next up on his to-do list: a multi day bikepacking trip, and an e-bike race.
