Your cycling helmet offers a great opportunity to improve your aerodynamics because it meets clean air. The way that the air is separated, passes over it, and meets again behind it is entirely down to its shape. By contrast, your rear mech, for instance, is in such turbulent air that gains are almost impossible and most brands ignore it in their aero quests. Switching your standard road helmet for an aero road model will save you around a minute on a 40km bike leg.
There’s no disputing that the coned time-trial (TT) helmet is the fastest option. In our tests the best of them can save a further minute over even the quickest of this group. But TT helmets are typically heavier, hotter and for race day only. A £250 TT helmet is a big investment when it only gets worn a few times per year.
Aero road helmets can – and should – offer a balance between TT and road helmets. That is, they have to be faster than a road helmet yet free from the compromises of weight and ventilation of a TT helmet. An aero road helmet that’s hot and heavy, yet not as aero as a TT helmet, is pointless; you may as well go for maximum aerodynamics. So while aero speed is really important here, we’re also looking for a helmet that you can train in and use on hot, hilly events.
Ease of use in transition is less of an issue than with TT helmets but the best buckle designs can help you. We’re looking for fumble-proofing – it isn’t about how fast you can close them but how many times out of 100 you nail it.
How we tested
Our testing combined empirical and subjective elements. We rode in training and races and noted the comfort, fit and ventilation. We also practised getting them on and off in a hurry – the differences between these helmets are small and they could easily be wiped out by a clumsy transition. We gathered aero data for every helmet on a 7km loop, using a power meter and a lap split view on a Garmin to hold an average power of exactly 250W for each ride. We maintained the same riding position and clothing throughout. We also drew on some wind tunnel testing carried out by our sister titles Procycling and BikeRadar. The differences between most of these helmets are small – 5secs covered the top five in an 11-minute test – so weight and ventilation are at least as important as speed.
For a helmet designed with real wind tunnel R&D, the Rivet looks to be incredibly good value. The only suggestion of cost-saving is in the partially in-moulded construction, which leaves some of the EPS core exposed, but all that means is that you have to look after it a bit more – don’t literally throw it into your car. The retention device is height adjustable through three positions, helping to deliver a secure, snug fit.
It feels a little odd to start with because the brow pad is split into a centre pad and temple pads. On the road this is quickly forgotten, so give the Rivet a chance if you try one on. The huge vents and deep internal channels blast air over your head. It’s fast, too, just one second off the Scott and five from the Specialized. The downside is the chunky 340g weight.
Verdict: Great value, fast and very airy, but a bit heavy compared to the lightest here 92%
We tested the Manta more thoroughly than we intended. Not only did we race in it, we also crashed in it! Despite nutting the tarmac pretty hard we were able to get back on quickly and finish, without even a headache. That probably says more for modern helmets in general than the Manta specifically. Either way, we weren’t going to repeat the exercise in each of these.
The 251g Manta is the lightest here by a big margin – the Mavic, at 276g, and the 290g Scott are the only two others under 300g. The ventilation is also good. While rivals with huge front vents offer even more airflow, we were comfortable racing in the Manta on a warm day. The fit is great, too, so it’s a shame that it was only sixth in our timed test, albeit not far behind at all.
Verdict: Superlight all-rounder that’s pipped by the best for venting and speed 89%
The Air Attack started the aero road helmet revolution… and also gave the genre a bad reputation for styling. It looked like a skate helmet when it launched and still does. Despite appearing solid, its weight is a middling 321g and the ventilation is good. It’s also one of the fastest lids here. We didn’t get on with the fit, finding the shell oddly round and the retention device lacking in its range of vertical adjustment, though it likely suits some riders.
The visor is shallower than we’d like, allowing wind to rush past your eyes, but it keeps out debris and offers good visibility when your head’s down. The magnetic mounts aren’t as snappy as the new Aerohead, and not so fumble-proof, but you can leave it inverted until you’re clear of T1 and then flip it one-handed.
Verdict: Expensive and quirky but fast, clever and tri-friendly 84%
Continue reading our guide to this year's best aero road helmets (2/3)