When it comes to the best road bike helmets, few names spring to mind as quickly as Giro. Founded in 1985 by Jim Gentes, Giro pioneered the concept and contributed to the prevalence of bicycle helmets in the peloton before they eventually became compulsory. Jim’s love affair with cycling and design gave rise to the original Giro Prolight helmet. It was avant-garde at the time, featuring both ventilation and aerodynamic properties, lightweight EPS-foam construction and a design that appealed to the masses.
Long before helmets were made compulsory by the UCI, Giro was already an established brand, having celebrated major success throughout the ‘80s and ‘90s. It was Greg Lemond who showcased the aerodynamic and performance benefits of the helmet - the Giro Aerohead, when he famously snatched the yellow jersey from Laurent Fignon in the final time trial of the 1989 Tour de France.
The past decade has seen helmet technology progress even further with lighter, brighter and safer technologies coming to the fore, such as MIPS, a Swedish innovation that protects the brain against the rotational motion caused by crashes or collisions. It comes as no surprise that Giro was an early adopter of this technology, having worked together with MIPS in developing ways to make its helmets safer and more comfortable to wear.
So if you're in the market for a new Giro road bike helmet, here's a full range overview to help you decide which is the one for you.
Giro road bike helmets
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Sharing a large portion of its design DNA with the Synthe, the Giro Aether represents the zenith of Giro’s contemporary road helmet range.
The key differences between the Aether and its siblings is the manner in which Giro has managed to seamlessly combine attributes such as performance, comfort and safety.
It employs the latest iteration of MIPS called Spherical technology: a two-part, dual-density foam built-in to the helmet that redirects energy during angled impacts.
The Aether follows very much a form-over-function approach in terms of aesthetics, with shatterproof, transparent arches running perpendicular to the venting slats for improved structural integrity and visual clout.
For more details, check out our Giro Aether MIPS helmet review.
Giro Syntax MIPS
The Giro Syntax MIPS offers a host of features usually reserved for helmets twice its value, while standing head and shoulders above its rivals. It's a well-ventilated and low-profile helmet that looks good and feels comfortable.
Seven premium colourways are available to match any style or preference. Visually, the Syntax looks aggressive, with 25 large vents that provide both an aerodynamic and cooling effect.
Like most helmets in the Giro range, it benefits from the Roc Loc/MIPS retention system. At 260g (medium), the Syntax also represents a happy medium in terms of weight, coming in lighter than the more premium Vanquish.
Giro Helios Spherical
Reasons to buy
Reasons to avoid
Giro's Helios Spherical helmet is designed for use both on road and off, making it a great option for anyone who likes to zip along tarmac while knitting together multiple gravel segments.
It comes with MIPS spherical tech, and features 15 ventilation openings for natural cooling. Inside you'll find antimicrobial Ionic + cushioning for absorbing sweat and maintaining comfort, while the whole thing can be adjusted with the brand's Roc Loc 5 Air system.
At home in a road race, cyclocross race, or on a gravel adventure, the Helios is one of Giro's most versatile road helmets in its range.
The Giro Vanquish is an out-and-out race helmet offering improved aerodynamics and a comfy fit. It also uses MIPS, which has been neatly and effectively integrated into the Roc Loc Air fit system so as not to alter the fit.
Designed to deliver greater depth and contrast to your vision, the removable Zeiss-developed lens can be stowed away by flipping it upside down or ditched entirely for regular shades, it’s your choice.
The progressive design has positioned it more as an everyday lid rather than an event-specific helmet, but the lack of ventilation could pose an issue when used throughout the warmer months.
Giro Synthe MIPS II
It might be over five years old now, but the Giro Synthe has earned a reputation for its stellar looks, comfortable fit and performance-orientated bent.
Featuring no less than 26 cooling vents Giro claims it’s more aerodynamic than the esteemed Air Attack, the predecessor of the Vanquish — which comes down to the use of some clever airflow trickery around the helmet’s frontal area.
The biggest drawcard is the improved Roc Loc Air fit system which supplies three different height positions to accommodate a broader range of head sizes as well as a better fit with less restriction around the contact areas.
The Synthe’s proven reputation at the pinnacle of the sport makes it a no-brainer for those looking for marginal gains.
The Cinder offers a lot more than a comfortable fit. For starters, it looks more like a Synthe 2.0 than brand-new design but closer inspection reveals several cost-cutting differences like Giro vinyl stickers and the absence of honeycomb mesh on the flanks. But to dismiss the Cinder based purely on a few visual discrepancies could be considered a mistake.
Utilising a Roc Loc 5 retention system, the Cinder is close to Giro’s best-fitting helmet thanks in part to the MIPS cradle system slotting in behind the foam padding.
At over 300g, it’s a little on the heavy side but what it gains in grams it makes up for in style, performance and fit.
Giro Agilis MIPS
The Agilis MIPS steps beyond the road, combining design cues from the Synthe and Giro's mountain bike range to create a road styled helmet with increased levels of protection. This extra coverage extends down the rear of the helmet for protection against impacts caused from rocks, roots and other off-road debris.
As expected Giro's Roc Loc system is used for retention and the helmet utilises MIPS to address rotational-impact forces. The vents may be smaller compared to other Giro offerings but they are plentiful with 36 slats positioned across the helmet and linked up with internal channelling.
Giro Isode MIPS
Whether you're new to road cycling, more of a commuter, or just not wanting to spend a huge amount of money on the latest tech, Giro's Isolde is an excellent budget-friendly and entry-level option. It's the most affordable MIPS helmet in the range, and its simple design makes it versatile enough to use in varying situations.
It comes in one universal size, and uses the Roc Loc Sport MIPS adjustment system to help you achieve the fit you need. It also features reflective details for visibility in low light conditions, quick-drying internal padding, an insect net to keep critters out of your locks, and a ratchet lock for easy securing.
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Mildred joined as Reviews Writer for Cyclingnews and BikePerfect in December 2020. She loves all forms of cycling from long-distance audax to daily errand-running by bike, and does almost everything on two wheels, including moving house, and started out her cycling career working in a bike shop. For the past five years she's volunteered at The Bristol Bike Project as a mechanic and session coordinator, and now sits on its board of directors.
Since then she's gone on to write for a multitude of cycling publications, including Bikeradar, Cycling Plus, Singletrack, Red Bull, Cycling UK and Total Women's Cycling. She's dedicated to providing more coverage of women's specific cycling tech, elevating under-represented voices in the sport, and making cycling more accessible overall.
Height: 156cm (5'2")
Rides: Stayer Groadinger UG, Triban RC520 Women's Disc, Genesis Flyer, Marin Larkspur, Cotic BFe 26, Clandestine custom bike