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Giro Prolight helmet



Light, expensive, superb… maybe it doesn't look expensive enough?

The new Prolight from Giro is, they claim, the lightest helmet that has ever been produced. At 175g, but does light weight mean a better helmet?

The Prolight which will be available in the UK this month had its premier pro outing on the mountain slopes of stage 7 of the 2009 Tour de France from Barcelona to Andorra Arcalis. Everything about this helmet is new except for the name.

Giro’s original prolight was launched in 1986 and was the first all EPS-foam helmet created by Giro founder, Jim Gentes. Time has moved on and as this new Prolight shows design is everything.

Riders from Astana, Rabobank and Garmin-Slipstream wore the Prolight during the Tour and they benefitted from a hefty weight saving over Giro’s other front line road helmet, the Ionos. The Prolight weighs an impressive 125g less than the Ionos, that’s nearly half the weight and the Ionos is hardly on the beefy side. My current helmet is a Giro Ionos and by comparison the Prolight feels and looks less bulky when worn.

The biggest weight saving has come from a complete overhaul of the tried and tested ‘Roc Loc’ retention system. The Roc Loc 4 featured on previous models has plastic moulded teeth and a slider bar to easily adjust the straps to fit your head correctly. The new system, dubbed Roc Loc SL , does away with the teeth and clip system and instead goes for a simple but ridiculously effective elasticated fabric band. The lightweight, fixed position webbing and the three position basket around the helmet is self adjusting for an extremely quick and comfortable fit. At first sight the fabric band and wire like plastic arms look incredibly flimsy but when in use the Prolight stays secure, comfortable and, due to its feather weight design, almost unnoticed.

To keep your head cool during warm climbs and long rides there are 25 large vents optimised under wind tunnel tested conditions to channel airflow directly where it needs to go. I found this worked well as, even in the hardest sprinted climbing sessions I didn’t sweat enough to have a problem.

At the end of the day all helmets have to pass the same stringent safety procedures (which is why the Prolight could be called the Pro(not quite so)light in the US of A where it will come in at around 200g due to tougher safety requirements. A £30 helmet has the same certificate to say it passed the same test as this £150 Prolight. You make your decision from there onwards based on fit, comfort, weight and perhaps looks.

So, fit: I had no issues at all. It was extremely easy to adjust and as it is so simple there were no complications when adjusting on the bike either.

Comfort: The elasticated band that crosses the rear of your head with ‘GIRO’ written into it is very effective. Why hasn’t this been taken up before? As it is soft it doesn’t press into your head but wraps around it without adding undue pressure.

Weight: Well it is certainly light. Is it the lightest? Specialized Piranhas etc from the mid 90s may come close but Giro’s claim for the lightest helmet available now certainly holds water.

Looks: Our test model (blue and black) was a subtle, unobtrusive finish but the red and black one certainly does a better job with the aesthetics. No doubt there will be a Livestrong flavour to get people reaching for their wallets too.


A fantastically light weight helmet at a fantastically high price. Paying £150 for a product that delivers to the same basic requirements of a £30 alternative seems nuts but if you do hours in the saddle, want want comfort when riding and dont want to overheat this is the helmet for you. If you have a carbon or titanium bike built from the best, priciest and lightest components why add 100g+ to the riding weight by having a heavier helmet?

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Make and model: Giro Prolight helmet

Size tested: M

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?

This helmet is aimed at the top level or road riders who ride a lot, enjoy it and don't mind paying to make iot even better. Giro say it is the lightest helmet available and it is super light compared to their other top end lids.

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

Switching the closure system on the helmet from a plastic Roc Loc 4 to the webbing and fabric roc loc 'SL' has shaved a substantial amount from the weight of the Ionos without sacrificing fit or comfort, in my opinion the Prolight offers superior levels of both.

Rate the product for quality of construction:

Didnt have any issues at all, how well the fabric will last when soaked in sweat or rained on for a seaosn or two remains to be seen though. That would be my only question.

Rate the product for performance:

I couldnt ask for more, it was light, kept my head cool and it didnt look stupid either which is a bonus. Obviously I was fortunate enough to have to trust the test certificates on safety so couldnt tell you that it prevented injury but I am sure it would.

Rate the product for durability:

Same comments apply as in the construction section, I question how long the elasticated fabric band will last. I only do this as I know elastic tends to perish after a while.

Rate the product for weight, if applicable:

Can I give anything but a 10? It is extremely lightweight. The prolight does what the name suggests. It is light and aimed at pros and those of us who like to pretend!

Rate the product for comfort, if applicable:

Felt great, I didnt even know I was wearing it most of the time which is eaxactly what I want from a helmet.

Rate the product for value:

£150 (rrp) is a lot to spend on a helmet but take into account the riders and teams that giro sponsor, the development that goes into a helmet, it all adds up. However, £150, in my opinion, is simply too much to pay for a helmet, even one as good as this.

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

It performed flawlessly. The lightweight design meant that my neck didnt get fatigued as quickly, that I could move around more freely and could ride as if it wasnt there.

Tell us what you particularly liked about the product

The fixture system around the back, usning an elasticated strap as a closure mechanism makes perfect sense and can surely fit a wide range of people.

Tell us what you particularly disliked about the product

The price, it is expensive and has no 'fancy' stuff like the Ionos. The other top end Giro helmets have a smattering of carbon fibre here and there but not the Prolight, yes I guess the carbon on the Ionos isnt necessary but it makes it look expensive wheras the Prolight could be mistaken for a £50 lid.

Did you enjoy using the product? Very much so

Would you consider buying the product? Yes, if I could find it discounted

Would you recommend the product to a friend? Yes.

Anything further to say about the product in conclusion?

A superb helmet that performs like it should, its only flaw is that its looks don't reflect its price tag

Overall rating: 8/10

About the tester

Age: 24  Height: 5ft 10  Weight: 66kg

I usually ride: felt ar4  My best bike is: i like my felt and my orbea ora tt bike equally

I've been riding for: Under 5 years  I ride: Most days  I would class myself as: Experienced

I regularly do the following types of riding: road racing, time trialling, commuting, club rides, general fitness riding, mtb, triathlon

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