Review: Giro Eclipse Pro Spherical Helmet

The Giro Eclipse Pro is a helmet designed for going fast. It’s the lid of choice for podium-bothering pro racers like Wout Van Aert and Pauline Ferrand-Prevot, where the difference between success and failure is measured in seconds, and even off-road: Kate Courtney chose the Eclipse Pro during her record-setting win at the Leadville MTB 100 in 2025.

Giro claim the Eclipse Pro is 17% faster than the previous Eclipse – “the result of deep collaboration with the world’s fastest pros, endlessly refined with CFD in the Giro lab and then proven in the wind tunnel.”

That’s quite a lot faster. It’s no secret that the promise of free speed holds just as much appeal for lesser mortals of the sportive/gravel scene as it does for the pros – there’s just less riding on the outcome – and we’ve been trying out the Eclipse Pro for a few months now.

We don’t have access to a wind tunnel at Sportive.com – unless you count that overgrown snicket down the street, which comes pretty close on blowy days – so we’ll not comment on the aero claims at 50kph. But, after 1000km of road and gravel, we’ve put together a good impression of the Eclipse Pro and whether it’s worth that £295 price tag.

Out of the box, the Eclipse Pro Spherical is a good-looking helmet. It’s well finished and surprisingly light in the hand – our size M (55-59cm) weighing just 282g. Giro point out that the Eclipse Pro is lighter than many competitor’s fully-vented ‘climbing’ helmets”, and it’s only a smidge heavier than the Giro Syntax (non-Mips) that I usually wear.

For an aero helmet, it’s also well furnished with ventilation ports. There are 14 in total, designed to help channel airflow into and through the helmet, and Giro say they are particularly effective at higher speeds typical of racing – or in my case, on descents. To the rear of the helmet, a discreet “tail” – that makes 15 ports if you count it as one – helps enhance airflow over the rear of the helmet without the try-hard appearance of those teardrop shaped helmets you see at time trials.

In fact it’s a pretty svelte and normal-looking helmet. Maybe the most striking feature visually is the helmet’s ‘Spherical technology’: a two-shell construction consisting of an outer shell (or liner, as Giro call it) attached to the helmet’s inner shell – the part that cradles your head – using a ball-and-socket connection. This allows the outer shell to rock a few degrees side-to-side, dissipating impact forces in the event of a collision.

We’ve not managed to test this in the field yet (touch wood), but it’s quite plausible to see how it might work just by gripping the inner part of the helmet in one hand and rocking the outer shell with the other. It’s impressive that Giro have managed to incorporate this, AND the aero features, while adding a mere 20g or so over the Syntax.

So we have an aero, lightweight and safety-optimised helmet on our hands. How does it feel to ride?

Putting on the helmet, the first thing that struck me is the fit. It’s absolutely superb: the cradle ratchets down with a few clicks for a perfectly snug, secure feeling fit. I like the fit on my Giro Syntax, but this is a level above – it is without doubt the most comfortable helmet I’ve worn.

On to the road then, and across a season of road and gravel rides in mixed April-June conditions the Eclipse Pro has been given a thorough workout. And it’s proven to be an excellent helmet, especially in cooler weather.

Most of my rides are solo loops averaging between 20-30kmh depending on route and whether it’s mainly road or gravel. So it’s safe to say I’m not hitting the warp speeds that would really draw maximum potential from the Eclipse Pro’s aero credentials. I can’t say I’ve noticed any speed gains, nor would I expect to, but what is noticeable is the difference in ventilation at higher speeds. On descents for example, you can feel those ventilation channels doing their thing, the air flow through the helmet becoming noticeable.

The counter to this is that during efforts, and at lower speeds – lengthy climbs for example – the helmet can start to feel slightly warmer than would be optimal. I don’t say this as a criticism – to some extent it’s unavoidable given the helmet physically contains fewer vents than something like the Syntax. That’s the deal with an aero helmet: you accept a small hit on the comfort front as a worthwhile trade-off in pursuit of speed. If you have an aero-optimised bike you’ve already made that decision, and a helmet like the Eclipse Pro makes sense as a logical next step.

Within the parameters of an aero helmet, Giro have taken every step to improve ventilation. That excellent fit I mentioned is down to their patented Roc Loc® 5.5 Air Fit System, which not only ensures a secure fit but also helps improve airflow by positioning the inner liner slightly above the skull. This has an additional benefit in that the helmet feels almost suspended above your head rather than weighing down on it.

Alongside this, what Giro call their “DryCore™ sweat management system” – a strip of padding across the front of the helmet – uses an internal silicone bead to redirect moisture away from the rider’s brow. It’s designed to prevent sweat from running into your eyes on hot days or climbs, and it seems to be pretty effective.

The padding has another trick up its sleeve too: Giro have incorporated IONIC+®, a mineral-based antimicrobial technology that permanently embeds pure, charged silver molecules into textile fibres. When exposed to sweat these silver ions are activated, neutralising odour-causing microbes and keeping your helmet feeling fresh.

All of which is to say, Giro have gone the extra mile to mitigate the effects of wearing an aero shell on your head. The results are borne out in the Eclipse Pro’s comfort, and while ventilation is not on a par with a full vented helmet it’s unlikely to be a deal breaker. The overall quality and comfort of the Eclipse is such that it’s easy to recommend, especially if you’re of a competitive nature and looking for the optimal balance of fast and light.

A side note on the comfort front: on my first few rides I did experience the occasional sharp spot of discomfort at the base of my skull , especially when looking over my right shoulder. It felt as if the cradle was digging into my head, but only sometimes and only on one side – quite odd.

After comparing the cradle design to my Syntax and concluding they were basically identical shapes, I gave the contact points on the Eclipse the lightest of rubs with a very fine grit sandpaper. Problem solved: no more chaffing.

Overall, the Eclipse is an exceptionally snug and unobtrusive helmet, and one I have no hesitation wearing on all-day rides.

Conclusion

The Giro Eclipse Pro Spherical is a top quality, performance-oriented helmet for cyclists looking to eke out every last advantage in pursuit of speed without compromising on weight. It’s both aero and light – the dream combination – and also boasts an excellent fit, decent ventilation, and cutting edge safety features. Those are boxes most of us want to see ticked, so you may well consider the Eclipse Pro worthy of the high-end price tag.

Construction quality and finish is top-notch, as you’d expect, and it’s also a smart-looking helmet. We tested the “Stone” colourway, but the Eclipse Pro is available in a range of eight muted, natural colours – and flame red – so you’ll find one to suit your style.

There is a small price to pay in terms of overall ventilation on warmer days, and this may be something to consider on summer events like La Marmotte or L’Etape du Tour. But for everything else, the Eclipse Pro Spherical strikes an excellent balance between comfort, speed and light weight which makes it a really strong proposition not just for competitive cyclists, but for anyone looking to ride fast in style and comfort.