Giro Radix Mips Review

Giro has a long tradition of designing high-end mountain bike helmets, and more than any other helmet in their current lineup, the Radix Mips reflects that heritage in its design. A descendant of classic trail helmets like the Xen and Hex, the Radix is a modern take on an iconic shell shape. In a market where helmet styles have become ultra-specialized for specific disciplines, the Radix is a true all-arounder, and for that reason, we love it.

Impact Test

For the most heavily weighted metric of our review, we partnered with the ACT Lab to conduct impact tests in a lab setting, ultimately offering you more information as you shop for a mountain bike helmet. This option came in towards the middle of the pack in our assessment.

This option received an impact test score of 5.3, though it did pass the requisite standards set by the CPSC, making this still a worthy option if you're looking for a light and modest profile helmet.

Comfort

At this point, we've come to expect quality and comfort from any Giro helmet we test, but despite our high expectations, we were genuinely surprised at this model's comfortable, secure fit when we first tried it on. Many times, even the best models can take some getting used to before you're fully confident in the fit, but the Radix Mips almost seems to pop into place on your head and feel as natural as a baseball cap. With the harness tightened appropriately, the shell sits firmly in place without any pressure points or pinching, and the adjustable ear splitters manage the straps well and keep them away from your ears. Obviously, the fit will vary slightly for different head shapes, but we had a number of testers, as well as friends and family, try this model on with positive feedback across the board.

A confidence-inspiring fit is great, but it means nothing if the helmet starts to chafe or develop pressure points over the course of a long ride. We weren't surprised to find that the Radix stays comfortable no matter how long you wear it. During testing, we wore this model out on a few long-haul adventures and never had any issues. We actually found that all-day adventure riding is this helmet's bread and butter. The light weight and comfortable fit mean it tends to disappear on your head. Our only ask would be for a little bit more ventilation on hot days.

Ventilation

Despite a whopping 25 air vents and internal channels in the EPS foam, we found the Radix Mips left us wanting slightly in the ventilation department. It isn't a stifling helmet by any means, and among similarly priced helmets it performed well. Given its lightweight construction, though, we expected it to be a little bit breezier. On warmer days at low speeds the air starts to feel a little bit stagnant under the hood and things can get sweaty. Our leading theory is that the small vents just don't allow as much air to move through the shell and across your head, but we would be lying if we claimed to be experts in aerodynamics.

No matter how good a helmet's ventilation is, you're going to start sweating eventually. It can be annoying and dangerous to have sweat dripping out of your helmet and into your eyes or eyewear, so we pay very close attention to sweat absorption alongside ventilation. The Radix Mips has ample padding along the brow that does a great job of absorbing sweat and channeling it away from your eyes. While testing this helmet we didn't often find ourselves having to stop and clean salt streaks off of our sunglass lenses.

Usability

We gave this metric 15% of the total score of the Radix, which we scored based off features and ease of use. As you might expect from a mid-range offering, this model isn't loaded with all of the latest and greatest features and gadgets. It does, however, offer all of the basics required of a daily driver mountain bike helmet. The already-discussed Roc Loc harness, Mips rotational impact protection, and adjustable ear splitters make up the bulk of this helmet's feature package along with a light-duty adjustable visor. The visor isn't nearly as substantial as many modern mountain bike helmets, but it will help protect your face from light brush on overgrown trails and keep the sun out of your eyes when in the lowest position. Giro claims that it's possible to stow goggles on the front of the helmet with the visor in its highest position, but we tried it out and we wouldn't recommend it.

Without many bells and whistles, the Radix didn't force us to wade through much marketing fluff to figure out what kind of value it really brings, and that's a big part of why we found it so charming. Simply put, it's a mountain bike helmet, and it does the job nicely.

Weight

A lack of frills certainly contributes to this helmet's almost-ridiculous weight. At just 360 grams for our size large, it is among the lightest mountain bike helmets we've tested. In our minds, the Radix's weight is one of its biggest selling points. Typically, when it comes to cycling equipment, weight reduction comes at a premium. The lighter the gear, the higher the price. So, a lightweight helmet at a mid-range price without sacrificing quality is an exciting prospect.

Should You Buy the Giro Radix Mips?

If you're looking for a versatile, no-frills mountain bike helmet that you can use for all of your cross-country, trail riding, and light-duty all-mountain adventures, the Giro Radix Mips is an excellent choice. In a world where each new mountain bike helmet release has a longer marketing brief than the last, the Radix Mips bucks the trend.

What Other Mountain Bike Helmets Should You Consider?

The budget-priced Lazer Coyote KinetiCore is an excellent alternative to the Radix, which offers top scores in impact testing. If you're looking for an alternative that favors ventilation and pedal-intensive days, check out the Smith Engage Mips.