Expertly tested top rated 10 best aero road helmet reviews 2021 buyer reports & ratings. In this group test we’ve tested aero optimized road helmet get track tested for drag.
Advancing technology means that road-going aero helmets have become commonplace in the peloton. They’re well ventilated, have the same internals as a standard road helmet and style wise have few differences, making them an attractive option for many.
Reducing your aerodynamic drag via a streamlined helmet makes sense. Over a certain speed, 90 per cent of your effort goes into pushing air out of the way (drag) and the largest proportion of that comes from your frontal area, including your head and shoulders.
Each new aero helmet launch is accompanied by independent aero claims around its watt-saving credentials. However, your equipment is only part of the equation – how the airflow interacts with the helmet will be impacted by your own shape and body position.
To determine how big – or small – the differences are, we checked in with AeroCoach’s Xavier to test four aero helmets against one baseline lid, on two different riders. Rider one – measures in at 183 centimetres in height, with 48cm-wide shoulders, while rider two is 165cm tall with 37cm-wide shoulders.
Our data did show differences between the performances of the helmets between the two riders. However, helpfully for readers at home who don’t have access to these facilities, there was also one very clear winner.
The differences between the helmets’ aerodynamic performances were marginal, especially at slower speeds. At 30kph, the variance between the best and worst helmets was between two and three watts depending upon the tester; many riders may be happy to give this away in favour of choosing the helmet that’s most comfortable.
Best Aero Road Helmets
- Lazer Bullet 2.0 Aero Road Helmet
- Bontrager Ballista MIPS Aero Road Helmet
- Giro Vanquish MIPS Aero Road Helmet
- Specialized Evade II MIPS Aero Road Helmet
Turn up the speed to 45kph, though, and the differences jumped to between nine and 10 watts, which is a more significant gain. The helmets on test were the Specialized Evade, Lazer Bullet, Giro Vanquish and Bontrager Bullet.
Our baseline helmet was Met’s Trenta – a middle-ground helmet that’s less optimized for cutting drag than Met’s dedicated aero lid the Met Manta.
The Trenta actually turned out to be pretty fast but it still serves as an effective baseline and all wattage savings (or otherwise) listed are a comparison to the initial run in the Trenta, with hands on the tops of the bars.
We carried out the test runs at Newport Velodrome, a favourite haunt. “We do testing using the Garmin Track Aero system. This is made up of hardware and software that allows us to track your coefficient of drag (CdA) as you ride round the track,” he explained.
During the testing, we ran control repeats to account for changes within the velodrome, and to ensure riders were holding a consistent position.
In order to increase rider consistency, we used two defined positions – riding on the tops and drops, with straight arms in both cases. “Locking out your arms means it’s more consistent, a slightly bent arm is less so because you may bend it more or less between runs,”.
On the tops, we experimented with turning our heads to the side each lap, to simulate a rider who is moving around a lot on the bike, then on the drops we tried both a neutral and dropped head position, simulating fatigue or a sprint.
We’ve listed wattage savings at 30kph and 45kph.“Wattage savings at 45kph are going to be higher at 30kph in still conditions but if you’re riding at 30kph into a headwind, the relative air speed is higher, so being more aerodynamic is important and it starts to look like you’re traveling at 45kph in still air,”.
Lazer Bullet 2.0 Aero Road Helmet
The Lazer Bullet is a feature-packed helmet. It comes with an ‘Airslide’ honeycomb vent, which can be ridden open or closed – the latter allowing for greater airflow.
There’s also an add-on in the box, in the shape of a solid replacement for the honeycomb insert. The closed-off, solid option is advertised as being designed in collaboration with Lotto-Soudal “primarily to provide an edge in sprint finishes”.
Since most amateurs are likely to place importance on breath-ability over competition in WorldTour sprints. We tested the helmet at the middle ground – with the honeycomb vent fitted, but closed.
As with the Giro Vanquish, the Bullet also comes with a specific visor to be used with the helmet, which would improve its aero qualities even further for the rider wanting to use the helmet for a TT.
However, in order to keep the comparison with other helmets as fair as possible we opted not to use it during testing. A small frontal area and teardrop profile aims to improve the aerodynamics.
Adjustment is operated via a rear dial, and there’s a rear light fitted to the back for a little additional safety. The Bullet proved to be the heaviest the helmets on test, probably down to the additional features included, so both testers were more aware of the helmet during testing.
The Bullet 2.0 is the only helmet on test not to feature a MIPS or similar safety feature as standard, though this is available under $300.
The back of the helmet is quite closed off by the retention cradle, which didn’t allow our long-haired tester to feed a ponytail (or aero plait) through, and the wings of the cradle also dug in a little bit.
We believe the helmet would perform better with the solid cover in place, commenting: “Our recommendation would not be to use the vents closed, because it didn’t come out very fast.
“I reckon if we did redo the test, using the smooth cover, or even with the vents open, it would perform differently and I would expect slightly better.
Bontrager Ballista MIPS Aero Road Helmet
One of the most obvious claims to fame for the Ballista, is that it was the helmet used by Jens Voigt during his successful 2014 Hour record attempt.
It was tested in the wind tunnel, and placed side by side with the Specialized Evade, there are certainly similarities in the overall shape. On test, we adopted it as a go-to racing helmet, finding the breathability to be more than sufficient for hard efforts, even in the summer.
The three vents do provide less airflow when compared with a standard helmet but we never found the venting to be insufficient. One bugbear is that with its three large vents, there’s not an obvious sunglass port, which can be annoying if you need to remove your glasses and want to keep them safely stowed.
The internal AgION padding is antimicrobial, meaning the helmet doesn’t get as smelly. The padding is removable too.
We found the fit to be comfortable for both riders. Bontrager has added a MIPS layer to this design, in keeping with most of the helmets within the test and ticking a safety box which is important to meeting consumer expectation.
The Bontrager Ballista scores high marks for values under $150, is a lot of money, but for a wind-tunnel designed helmet used by top professionals, it is significantly cheaper than equivalent products from competitor brands.
What’s more, the quality is right up there and it’s pretty light too. Aerodynamically, the Ballista didn’t prove to be the fastest for either tester, but it wasn’t a slouch indeed riding in the drops in the head-up position.
Giro Vanquish MIPS Aero Road Helmet
The Vanquish has been worn by some prestigious riders, including Mark Cavendish, and it’s been designed following wind tunnel testing and extensive computational fluid dynamics analysis.
It aims to be a compromise between a road helmet and a specific, aerodynamic TT style helmet. You can choose to ride it with or without the visor. Since most people aiming to train or compete in road races will opt for without, we tested it in this configuration.
The Giro Vanquish’s outer shell has been almost split in two, with the largely featureless front portion designed to look like it wraps over the smaller and narrower rear half.
This wrap is something Giro calls TransformAir and the step down acts to trick air into behaving as if the helmet has a traditional teardrop TT shap but actually allows for a more practical shell design.
Four forward facing vents are employed to do the job of pulling cooler air over your head and these are complemented by six further vents at the rear, designed to dispel warm air and regulate head temperature.
We found these to be very efficient; it’s nowhere near as airy as a pure road helmet, but you can feel the vents doing their job and internal channeling works well to release warm air and sweat.Inside, Giro has employed the latest MIPS safety liner, and the liner is made of a much more breathable material than previous versions and has no noticeable negative impacts on the fit or comfort.
It also incorporates Giro’s longstanding Roc Loc retention system and antimicrobial pads to create an environment that is an absolute pleasure to put on your head. Without the visor, the Vanquish didn’t stack up well, being the worst performer.
Specialized Evade II MIPS Aero Road Helmet
The Evade is a longstanding member of the Specialized helmet line-up, and it has received several makeovers. The last major overhaul was in 2018, and since then the brand has added a MIPS layer as well.
Specialized says that the most recent version of the Evade is six seconds faster over 40kph versus the outgoing model. It’s also got an improved ventilation system, with 12 vents in total.Both our testers found the Evade to be extremely comfortable.
It’s also very breathable, and didn’t even leave hot-headed after a week riding in the mountains around Denia/Calpe, in Spain When it comes to safety, as well as the added MIPS layer, the Evade II has a patented energy optimized multi-density EPS construction and an aramid-reinforced skeleton designed to protect your head in the event of an accident.
You also get the ‘ANG add on which, when activated via an external app, can alert loved ones if you do have a crash. There’s a ‘Gutter Action Brow Pad’ to channel sweat away from your eyes, plus a micro dial at the back and the brand’s famous ‘Mindset HairPort II’.
The dial is easy to operate and our long-haired tester found the fit worked well. When it comes to closure, the brand uses a magnetic clasp below the chin. This feels premium, but we do wonder over its safety.
Though not the best in every single circumstance, when we averaged out the four positions, the Evade was a clear winner. It was the fastest for the one in the drops, and in the drops with his head lower, while for other it was fastest overall when riding on the tops.
Conclusion
For the best best aero road helmet, Specialized Evade wins hands down. he first thing we noted was that at 30kph, the differences between the best and worst helmets were marginal – in the region of two to three watts. This increased at 45kph to the region of nine to 10 watts.
Choosing the helmet that’s the most comfortable could be a bigger all-round performance gain. However, in any numbers game, there’s always going to be winners and losers.
For our smaller tester, the Specialized Evade was the fastest on the tops, the Bontrager Ballista was fastest on the drops, and interestingly the Met Trenta was the most efficient when in the drops with a low head position. If we average all of the numbers out, the Specialized Evade performed the best.
The Lazer Bullet was the worst for her, across all tests, with the Giro Vanquish second worst. On our taller tester, the Met Trenta was very marginally faster when on the tops.
However, the Evade was fastest in the drops and in the drops with a lower head – so again the Evade would be the most aerodynamic choice for him. When we average the results across positions, the Giro Vanquish was the slowest helmet.
It’s important to remember both the Vanquish and Bullet would likely be faster with the visor and aero cover respectively. A special mention has to go to the Met Trenta (£220) – which held its own, it is an optimised helmet, but it’s not the brand’s dedicated aero lid.
While we did test the effectiveness of the different helmets when riders moved their heads around, we found no significant differences between any of the models. There were differences between individuals, but without the expertise we had available to us, it would be hard for individuals at home to collect data on the most optimal helmet for them.
“Reading up on data that’s been published – for example the testing we’ve done here – is a good way of establishing the differences and best performers. The take-home message from today, was that the Evade is a good helmet, so from this data, that would be the one I’d recommend.”