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Giro Ionos (Garmin-Slipstream limited edition)



Superb performance level helmet, and team colours cost the same as the standard lid

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 Ionos is a range topping helmet aimed at experienced, high level road cyclists. The limited edition Ionos lid in Garmin Slipstream team livery tops out the Ionos range (there's also a limited edition lid in Astana colours) there is now no difference on the suggested retail price between it and the standard model which is also £159.99.

The Ionos is the result of three years research and development and Giro say it's the most technologically advanced road helmet they have ever created offering ground breaking (not sure that's the best phrase to use when talking about helmets - ed) levels of ventilation. It certainly delivers on its promise of extra air-flow. But for £160 so it should.

Our test lid weighed 320g, not the lightest but it's comfy enough that you don't notice it. I would prefer to ride in a well designed, well ventilated helmet any day of the week over a slightly lighter but uncomfortable one. The focus here is on light weight, improved fit and enhanced ventilation. Managing the balance of improved ventilation through larger air vents while maintaining or improving safety levels through the core structure is difficult and Giro have employed various new and refined technologies to increase airflow while still keeping you safe.

 Helmet fit is always a matter of personal opinion and it is always best to try before you buy. I can say that Giro do tend to offer the best fit for my particular head shape and their Roc-loc system has always offered comfort, adjustability and reassurance. Giro have been making a lot of noise about their new Roc-Lock 4 system and it is certainly quick and easy to adjust, even on the move, without you really knowing it is there. Giro have also included some other new technology. Their X-Static helmet pads offer improved antibacterial properties which say Giro will help it to limit odours and extend the useful life of the Ionos – sounds good although only time will tell on that one.

 The 21 vents that penetrate every surface of the Ionos make for a big air flow. The cooling properties of this helmet are increased by the huge vent at the front of the helmet and brand new exhaust system to allow hot air to escape to the rear. The Ionos is certainly the coolest helmet that I have tested and is a noticeable improvement on my previous top end helmet, a Met Inferno – Giro claim that it is 15 per cent better than their Atmos helmet, the previous class leader in terms of ventilation.

 In fact the Ionos is so effective at keeping your head cool that when it's chilly the helmet leaves your head uncomfortably cold. Luckily Giro have remedied this by supplying a thin, cushioned piece of shaped fabric to act as a layer of insulation on the front of your head. It’s an odd paradox that Giro have developed a helmet that is so effective at keeping your head cool that they need to supply a natty skullcap to help keep it warm at the same time. I am sure that the true value of the massive vents on the Ionos will become apparent come Spring/Summer.

 In a similar way to another top end Giro road helmet, the Atmos, the 2009 Ionos utilises a carbon and composite sub frame with Kevlar strips used to cover the exposed material and it looks good too. A plethora of composite weaves and internal strips of both carbon fibre and fibreglass composite further increase the strength of the helmet while keeping the helmet's weight down. The outer shell is fused to the internals of the Ionos to give a tidy, durable finish.

 The Ionos is expensive, there's is no getting away from that. In terms of crash protection your money buys you a helmet certified to CE EN1078 – the top European helmet standard, but certainly not the most stringent in the world. The extra cost of a helmet like the Ionos buys you extra ventilation rather extra protection – a thirty quid lid like the Bell Solar wil give the same level of protectionn.

While it's sat on top of your head waiting to be called on it keeps your head cool, comfortable and your ride relaxed. If you have the money and the right shaped head, it's a good buy.


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Make and model: Giro Ionos (Garmin-Slipstream limited edition)

Price: 160.00

Weight: 320g

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?

The Giro Ionos is a true high end cycling helmet aimed at experienced and enthusiastic road cyclists who are willing to spend big to get comfort and protection matched by no others. Giro say that this is the most advanced helmet that they have ever offered for sale with extreme ventilation coupled with striking style. I really do like this helmet, it looks good, feels very comfortable to wear and lives up to its claims about airflow performance.

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

The Ionos was actually released a season late, originally pencilled in for an '07 launch the finished product was not available until 2008. All of that research and development has come up with a lower profile, lighter, cooler and, giro claim, even safer top of the range helmet than they have previously had. Lightweight carbon composite materials are used in construction of the subframe for a very lightweight, safety concious result with huge vents for optimum airflow. Giro also use an 'in mold' technolgical system to fuse the four piece outer shell with the EBS (black polystyrene-like liner) in order to offer enhanced strength as both materials support each other for maximum safety.

Rate the product for quality of construction:

I tested the team slipstream limited edition version, I cant imagine that the differences between this and the 'standard' style helmets are any more than a colourway but I could find no fault. The helmet felt robust, strong and protective while being extremely light and so cool that my head was, at times, uncomfortably cold.

Rate the product for performance:

As previously mentioned, the cooling aspect of this product is incredible. I have worn well ventilated top of the range helmets before and this one knocks them into touch. It speaks volumes that in the pack that arrives with the helmet Giro enclose a thin, padded, shaped layer of fabric to act as a barrier between the wind and the surface of your head because the Ionos is so good at channelling cool air through the helmet.

Rate the product for durability:

Having used the helmet for around 350km of riding in the past week or two I have found no problems with durability. I have begun to expect niggles with any product to be visible within a few days of the first use just due to teething problems but not so here, nothing is loose, nothing looks used at all and the X-Static internal pads have worked a treat so far in keeping the Ionos feeling fresh.

Rate the product for weight, if applicable:

Admittedly it is not the lightest helmet around but it is certainly up there. It is light enough for me to not notice that I am wearing it, the fit is great and due to the low weight it simply slips your mind that you have it on.

Rate the product for comfort, if applicable:

Giro's roc lock 4 system does the job of gripping the head excellently. The system can be adjusted with one hand while riding should it not feel quite right and due to the system having so many tiny plastic teeth the fit options are vast. The low profile design of the helmet itself means that it can fit snugly around the top of your head without looking 'oversize' as so many helmets can.

Rate the product for value:

This is a £160 helmet offering the same level of protection as a £30 helmet, so you're not any safer. Obviously it's light, comfy and cool but you couldn't really say it was great value, especially as you're paying £30 just for a paint job.

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

As a helmet it offers high levels of protection and when riding the airflow through the massive front vents and newly designed exhaust system really does keep your head icy cool which is perfect for a long day in the saddle.

Tell us what you particularly liked about the product

I was won over by the fit of this helmet. The shape was perfect for my head and the roc loc system kept it securely in place.

Tell us what you particularly disliked about the product

Not much really, the standard colourway costs £130 which, to me, is a good deal. £160 for a team edition is excessive and the extra £30 doesnt make itself evident in anything other than finish.

Did you enjoy using the product?: Yes

Would you consider buying the product?: Yes

Would you recommend the product to a friend?: Any keen rider should, at the very least, give it some consideration

Your overall verdict of the product taking everything into account

A superb blend of style, design, technology and fit. The Ionos is as good as helmets get and there is nothing that I would change about it. A strong, secure fit that works perfectly with the 21 large vents to channel air around the head to keep temperatures down and make cycling far more comfortable.

Overall rating: 9/10

About the tester

Age: 24  Height: 5ft 10  Weight: 66kg

I usually ride: at the moment my Orbea Ora tri/tt bike  My best bike is:

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, touring, general fitness riding, mtb, triathlon

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