Bolle The One Premium helmet review

Bolle The One Premium helmet review

Is Bolle’s The One the only helmet you’ll ever need?

Words and kinda ok photos by James Raison
Really nice photos by Oliver Armstrong

Poking around the Tour Down Under Village I came across a very distinctive looking helmet I’d never seen before from French eyewear experts Bolle. It’s called The One; an appropriate name for a helmet trying to replace your entire collection of foam lids. No doubt it’s an ambitious product, and truly the strangest helmet I’ve ever reviewed.

So, let’s jump in and see what’s what.


What is The One? It’s kind of… everything.... It’s a ventilated helmet, an aero helmet, an MTB helmet, and a deep winter helmet. The One’s main party trick is the two removable covers that reveal 17 vents and turn it from an aero to standard ventilated helmet. That’s not all; the box also contains a removable peak, a removable LED light that slots into the rear of the helmet, and a winter padding set that acts like a fleecy skull cap. There’s even a “Sunglass Garage” in the front to park your eyewear when riding.

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What’s the price of all those helmet options? $260 AUD. That’s a compelling price if The One successfully all those helmet formats.


One of the first things I did was drop The One onto some scales because I’m an insufferable weight weenie like that. With covers on it’s a 330 grams and 260 grams without.

I did notice the extra weight in aero mode because its distribution is further forward thanks to the covers than fully ventilated helmets. So it’ll feel a bit hefty during a long stem chewing session. A 330g helmet is on the heavy end of the spectrum for road helmets, and is heavier than purely aero helmets without removable bits. For reference, my (not purely aero, but an aero/vented crossover) Kask Protone, that I consider a little portly, tips the scales at 290g.

I added up the weight of all the options too; the light was 15g, winter padding 36g, and 14g for the visor. Running the helmet in winter-aero-MTB-light mode would add up to around 390g depending on the weight difference between the summer and winter pads.

So The One’s weight; quite light with no attachments, a little heavy in aero mode, and quite heavy for a road helmet with all the optional extras.


The One is a serviceably comfortable helmet with a balance of strengths and weaknesses.

The rear cradle only has two positions roughly 10 mm apart, changed by pulling out pressing in a plastic stud. Most premium road helmets have a sliding system with a few centimeters of movement to get the cradle exactly where you want it, so The One is limited by comparison. Luckily I like a low cradle because that’s really the only option here. Those who like a high cradle might struggle to get the position they want. Cradle tightening is done with a rotating dial is used to crank tightness on and off with ease.

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The strap and adjustment system is quite rudimentary. Each strap runs all the way from the shell, through clamps that sit below your ears, and through the chin straps. It’s a departure from most high end helmets that use fixed straps that exit the shell and meet beneath your ears, and then have an adjustable chin strap for tightening. The One’s system took a lot of fiddling to find the right strap length and putting the clamp in the right position and it still doesn’t sit as nicely as other strap systems.

Comfort gets better with plush padding clustered on your forehead, making the front of the helmet very comfortable indeed. The rear shell has no padding at all, with Bolle opting to add a strip of pad to the rear cradle instead. There weren’t any sore spots or pressure points at the rear of the shell in the absence of padding so it averages out to be decently comfortable.

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I fit into a Medium (54-58 cm) and was towards the outer limit of that size. It’s a more rounded helmet than I normally wear, measured from front to back, and side to side of the inner shell. It was snug on the front and back of my head, with more room on the sides.

On balance I found fit and comfort to be fine. No complaints or uncomfortable pressure points but no high praise either.


Frontal vents are packed in tight, limiting airflow into the helmet. Chunky rear vents help effectively clear the air across the top and rear of your head

Frontal vents are packed in tight, limiting airflow into the helmet. Chunky rear vents help effectively clear the air across the top and rear of your head

Airflow through The One, with covers off, is something of a mixed bag. The frontal vents are compromised in size because they need to fit under the cover, and there’s reduced ventilation down the side. That, added to the forehead padding, limits the splash of cool air directly at the forehead. The enormous vents on the top and the exhaust vents at the rear are much more effective than anticipated at moving air over the top of your head. Even the sunglass garage vents pull a pleasant quantity of air around your temples and the side of your head. On balance, I was surprised at how well The One performed at cooling. I’d put it on par with a Kask Protone; ventilated well enough for most temperatures but a step behind purely ventilated helmets.

Frontal air ingress is limited by the small vents

Frontal air ingress is limited by the small vents

Covers on, the air moves through passably well if you’re at speed. Travelling at or over 30 kph makes the helmet very usable in warm weather. The sunglasses garage is the only entrypoint and it does well thanks to internal shape of the shell channeling air through and the rear vents sucking it out. If your speed drops, the temperature increases rapidly. Some steep climbs on warm days got quite toasty with plenty of sweat flowing down my face. I’d bemoan the lack of cooling if this were a pure aero helmet but The One’s removable vents mean the only person to blame is myself for choosing to ride with it covered. You can take advantage of the aero benefits climate permitting, or just deal with the heat in a race or time trial situation.

Considered as just a ventilated helmet, cooling and airflow is decent. Considered as just an aero helmet, cooling and airflow is better than expected if you keep air moving through. Considering it’ll do both, I was rather impressed at The One’s breeziness overall.


As always with aero gear, it seems my home wind tunnel is closed for calibration so I can’t verify any aerodynamic advantages for The One, and Bolle haven’t got any data anyway. Y’know what? I’m fine with that. Most aero helmet makers don’t give aero data anyway, and those that do publish data are usually extrapolating wind tunnel tests to “real-world” savings of x seconds over x kms at x average speed. I do trust that aero helmets give performance benefits but I find those sort of tests disconnected from how most people ride.

So I’ll defer to who tested The One with and without covers and found 8 Watts saved at 40 kph and 20 Watts at 50 kph with covers on. So is it aero? Dunno. Those tests do show that it’s more aero with covers on which makes the extra sweatiness feel justified.


The One’s included LED is, on paper, a cool feature. It replaces a Bolle logo in the rear exhaust vents that you can shove out when a pen. There’s no info or specs on the light but it’s got a basic 4-LEDs inside a red reflector. It runs on a CR2025 battery and has a solid and flashing mode.

It isn’t very bright, only putting out a few lumens but its reflector case does help when splashed with car headlights. I’ll be dropping it in permanently when Winter rolls around again though because the extra light and reflectiveness will add some visibility on those dark nights and mornings.


The One has interchangeable padding with standard warm weather pads removable for a warm skull cap. My test package from Bolle arrived mid-January during a historic heatwave and some months before Adelaide gets cold enough to warrant adding warmth. I’ll have to defer those tests to the future.

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I can confirm though that The One is brilliant in the wet. I wore it on a depressingly damp day and was stoked to find very little water ingress. A few drops snuck into the sunglasses garage but that was all from a lot of drizzle and 15 minutes of heavy rain. I arrived at my destination with a basically bone dry head and everything else saturated. I’ll be reaching for this helmet a lot in winter because the reduced airflow and covers will be ideal.


The One has to be considered as a helmet system. It defies standard categorisation because of how much it does. While it’s not the best at any one thing, it gets compelling when you look at the sum of its parts. It’s comfortable enough, breathable enough, aero, holds your glasses well, and can take a rear flashing light for added safety. It’s a good price too at $260 AUD.

I’ve not really experienced a product like this before with such a range of strengths and weaknesses. It gets a recommendation from me because of its versatility, and those who buy it for multiple talents will get plenty of value out of it.

Disclaimer: This helmet was sent for review by Bolle Australia. It’s not paid and we don’t make any money from the sale of Bolle gear.