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Giro Sonnet helmet



A lot of helmet at a great price, with a fit system that makes it a joy to wear

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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The new Giro Sonnet helmet is the women's version of the men's Savant model /content/review/48763-giro-savant-helmet, which impressed us when we reviewed it last year. Like its counterpart, the Sonnet is a lot of helmet for a little price.

Coming in three colourways, none of them pink, it looks like a serious helmet. It weighs a highly reasonable 259g and boasts 25 vents.

I tested the Titanium/Turquoise option, a sort of matt gunmetal with mint-coloured highlights. It also comes in white and pale green, and my favourite - matt black with deep purple accents.

The vents are Giro's 'wind tunnel' ventilation system, designed to drag air in at the front and out of 'exhaust' channels at the back - cooling your head as it passes. I can testify to the effectiveness of the system - as the weather's got colder I've had to start wearing a cap under the Sonnet in the early mornings. On a hilly, summer ride, you'd be glad of the breeze.

The Sonnet is the kind of helmet you forget you're wearing a few minutes after putting it on. Well-positioned soft padding inside the lid absorbs sweat and prevents any embarrassing indentations on the forehead when you arrive at your destination, and the Roc Loc 5 fit system simply works.

Roc Loc 5 is a minimalist arrangement of flexible plastic struts and an adjustment wheel, but the real magic is that it's adjustable up and down, as well as just cinching around the head. It adjusts far enough down to accommodate a ponytail, and cradles the head just enough to feel secure without being restrictive. Giro describe their fit as 'Skull Hugging Luxury' and claim that the system fits 98 per cent of the world's population.

The helmet itself is very light for the price - thanks to inmould construction, where a tough polycarbonate outer shell is fused with the helmet's impact-absorbing foam liner, which supports a greater numbers of vents. The £199 Aeon, Giro's top-of-the-range road helmet, comes in at 222g - which isn't all that much lighter than the Sonnet.

When I first saw the Sonnet, my immediate thought was that the matt grey paintjob was reflective, and was quite excited about the thought. I was disappointed to find it wasn't, but that's a minor gripe when you weigh up the positives here.

As usual with helmets, it's impossible for us to comment on how safe they are, except to mention that it's certified to EN 1078, the current EU benchmark for helmet safety.


A lot of helmet at a great price, with a fit system that makes it a joy to wear. test report

Make and model: Giro Sonnet helmet

Size tested: Medium

Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?

"The Sonnet is a new addition to our Women's Series collection, offering an amazing fit for riders who enjoy great routes as much as a swift pace. The slim shape combines impressive ventilation thanks to 25 Wind Tunnel vents and the comfortable convenience of the adjustable Roc Loc 5 fit and stability system. And with the light weight and durability of In-Mold construction, it won't weigh you down."

Tell us some more about the technical aspects of the product?

IN-MOLD CONSTRUCTION In-mold construction fuses a tough polycarbonate outer shell with the helmet's impact-absorbing foam liner. The fusion process allows us to sculpt better ventilation systems, so In-mold helmets can be lighter and cooler than traditional helmets.

WIND TUNNEL™ VENTILATION Giro helmets are developed utilizing our proprietary Wind Tunnel™ ventilation system, which combines active vents with internal exhaust channels that thrust cool, fresh air over and around the riders head-while forcing heat and stale air out. This significant increase in air channeling makes a difference that riders will immediately feel and appreciate.

SUPER FIT™ ENGINEERING FOR BIKE HELMET A great helmet is so comfortable that once it's on, it virtually disappears. Our proprietary three-size Super Fit system is based on 'human scale factors' data and over 20 years of crafting helmets for the best bike riders in the world. The result is pure Skull Hugging Luxury™, a helmet that fits 98% of the world's population, yet looks (and fits) like it was custom made just for you.


After more than two-years of development, Giro introduces Roc Loc 5. This groundbreaking fit system provides an entirely unique user experience with an unmatched level of comfort, stability, adjustability and weight savings. With Roc Loc 5, you can easily dial-in both fit tension and adjust vertical position with a single hand. Just twist the dial for a tighter feel on rough terrain, then back it off a notch and relax across the flats or a warm climb. Even with these remarkable features, Roc Loc 5 is still nearly 40-percent lighter than its popular predecessor, Roc Loc 4.

Micro Dial: The heart of Roc Loc 5 is this ratcheting, micro-adjusting dial. A simple, two-finger twist of the Micro Dial opens or closes the retention system and each click is audible.

Three-Position Bracket: It's never been easier to change vertical positions and fine-tune fit. We incorporated a three-position bracket that features 15-millimeters of up/down movement. Like the Micro Dial, this system can be adjusted without removing the helmet. Carefully-crafted ergonomic arms are shaped to be as comfortable as possible, yet work flawlessly with Giro eyewear (what we call Super Fit engineering).

Dual Pods: These two panels are designed to firmly grasp the back of your head while comfortably cradling the occipital lobe.

Strap Baskets: With Roc Loc 5, your helmet straps are always right where you need them. Not to mention this strap basket brings a new level of comfort.

Rate the product for quality of construction:

Feels well-made and durable.

Rate the product for weight, if applicable:

A very good weight, particularly for the price.

Rate the product for comfort, if applicable:

The most comfortable bike helmet I've worn.

Rate the product for value:

Excellent value for such a lot of great features.

Tell us how the product performed overall when used for its designed purpose

Comfortable and felt secure.

Tell us what you particularly liked about the product

The excellent fit system.

Tell us what you particularly disliked about the product

Lack of reflectives

Did you enjoy using the product? Yes.

Would you consider buying the product? Yes.

Would you recommend the product to a friend? Definitely.

Overall rating: 8/10

About the tester

Age: 0  Height:   Weight:

I usually ride:   My best bike is:

I've been riding for:   I ride:   I would class myself as:

I regularly do the following types of riding:


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big mick | 11 years ago

Yea and fancy it could save your life

kie7077 | 11 years ago

I bet this only cost the manufacturers a couple of quid to produce, a bit of foam, a strap and a flimsy bit of plastic, what a ginormous rip-off.

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