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Trek Ballista Mips helmet



Comfortable and surprisingly breezy aero helmet that is well priced against the opposition
Micro-adjustability for a good fit
Good venting for an aero helmet
Impressive weight
Like most aero helmets, it's pricey

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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Trek's Ballista Mips is a lightweight aero road helmet that offers impressive cooling for such a small amount of venting. The retention system is easily adjustable, giving a great fit, and you get the bonus of Mips tech too. Like most aero helmets it's not cheap, but it is competitively priced against some of its main competitors.

For more options, check out our guide to the best aero helmets.

Aero gains, marginal gains... if you need them you're going to be looking for an aero helmet to go with your aero bike and your deep-section wheels. Unless you are a time-triallist or triathlete, though, where the aerodynamics are the most important factor over comfort and cooling, you are going to want something like the Ballista which offers a blend of them all.

> Buy now: Trek Ballista Mips for £229.99 from Trek

Trek says the Ballista is its fastest, most aerodynamic helmet. How fast? Well, without a wind tunnel that is pretty much impossible to say, and I am not going to sit here and talk about how I was so many seconds quicker over this section than when wearing a different helmet as there are just so many variables at play.

> Should you buy an aero road helmet? How much faster could you be?

When hunkered down in the drops as low as I could go, I did find the Ballista sat well, with the aero tail flat towards my back, and the front allowing good vision for looking forwards.

The dial system for adjustment uses just a small plastic section at the back, as opposed to a band running all the way around the sides of your head like on most top-end helmets. Here the helmet has a Boa wire (just like the Boa system on your shoes) to adjust the fit, and it does that with no pressure at all which makes for good comfort, as well as plenty of adjustment.

2023 Trek Ballista Mips Helmet - tension system.jpg

Attached to the main EPS section of the helmet you'll find the Mips Air system. It's a cradle lining the inside of the helmet and is a lightweight system that reduces the rotational forces that would otherwise be transmitted to the brain during impact from a crash.

> All you need to know about Mips

2023 Trek Ballista Mips Helmet - inside detail.jpg

With the Air system, the technology has been built into the padding, and according to Mips it allows 10-15mm of movement in relation to the EPS section of the helmet. If you didn't know what you were looking for, you'd never see it as the whole setup is very discreet.

2023 Trek Ballista Mips Helmet - inside.jpg

To keep things smooth, the Ballista has very few vents – just four in total – but their shape is designed to scoop in as much air as possible, and the helmet does draw a fair chunk of air through. You can feel it flowing over your head, and exiting via scoops out of the rear.

2023 Trek Ballista Mips Helmet - front.jpg

For the majority of the review period the weather was pleasant and early rides took place with the temperature around 20°C. The Ballista coped fine with hard riding in this sort of warmth, with that airflow passing through the vents. As the thermometer climbed up towards 30°C a few weeks later, though, I found the conditions too warm to wear it comfortably, especially when on a long drag or even a short, sharp climb. With minimal air blowing through at lower speeds, it did become quite stifling, the black finish probably not helping.

2023 Trek Ballista Mips Helmet - rear.jpg

I'd say that up to about the mid-20s the aero advantage is worth the compromise on the heat, but above that I'd switch to a vented helmet to keep cooler. The Ballista isn't really a helmet I'd grab in the middle of a heatwave.

For an aero helmet the weight is impressive, though even the chunkiest of aero helmets tend not to be heavyweights. It comes in three sizes, with this medium (54-60cm) weighing in at 271g on our scales. The small fits 51-57cm head sizes, and the large 58-63cm.

2023 Trek Ballista Mips Helmet - Mips.jpg

The overall quality is to a high standard and it's good to see the outer liner wrapping itself around any exposed EPS to reduce accidental damage from drops and the like. The two front vents that sit either side are spaced to accept your sunglasses arms too.

2023 Trek Ballista Mips Helmet - front vents.jpg


As for price, the Ballista has an rrp of £229.99 which isn't exactly a bargain, but then again, not many top-end helmets are. Against the competition it's actually quite competitive.

Specialized's S-Works Evade 3, which I tested last year, also uses Mips and the weight is virtually identical. It costs a fair chunk more, though, at £275, while the Kask Utopia Y that I tested last month sits somewhere in between the two at £245.

There are some cheaper options, though: the HJC Furion 2.0 that Ed tested last year is 'just' £180. It's quite a bit lighter, too, at 218g.


If you are after an aero helmet for road cycling then the Ballista Mips does a great job. It's a slimmed-down but similar sort of design to many time trial aero helmets, but with impressive airflow for the number of vents and without being hugely heavy. It's priced competitively too.


Comfortable and surprisingly breezy aero helmet that is well priced against the opposition

If you're thinking of buying this product using a cashback deal why not use the Top Cashback page and get some top cashback while helping to support your favourite independent cycling website test report

Make and model: Trek Ballista Mips Helmet

Size tested: Medium

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?

Trek says: "An aerodynamic road bike helmet that is undeniably fast, yet surprisingly light, cool and comfortable."

It does deliver a good balance of aeroness and airflow.

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

Trek's website states:

Trek's fastest, most aerodynamic helmet will save big watts and shave crucial seconds

An excellent ventilation system makes this aero helmet surprisingly cool and comfortable

The Mips Air system is light, cool and designed to improve comfort and protection

The single-lace BOA® fit system is fully adjustable to provide a custom, 360° fit

Rubberised sunglasses docking port provides secure and easy-to-use storage

Bevelled front edge improves field of view while riding on the hoods and in the drops

5-STAR Virginia Tech safety rating

The Crash Replacement Guarantee provides a free helmet replacement if involved in a crash within the first year of ownership

Rate the product for quality of construction:
Rate the product for performance:
Rate the product for durability:
Rate the product for weight (if applicable)
Rate the product for comfort (if applicable)
Rate the product for value:

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

The shape works well with aero road bike riding positions, and it provides good airflow.

Tell us what you particularly liked about the product

Impressive venting for the low number of vents.

Tell us what you particularly disliked about the product

Around the same as other top-end helmets; it's a lot of money.

How does the price compare to that of similar products in the market, including ones recently tested on

It's cheaper than the Specialized and Kask mentioned in the review, although the HJC is even better value.

Did you enjoy using the product? Yes

Would you consider buying the product? Yes

Would you recommend the product to a friend? Yes

Use this box to explain your overall score

A comfortable helmet thanks to a clever retention system and good airflow, and it is well made. It's good to see competitive pricing too (relatively speaking).

Overall rating: 8/10

About the tester

Age: 44  Height: 180cm  Weight: 76kg

I usually ride: This month's test bike  My best bike is: B'Twin Ultra CF draped in the latest bling test components

I've been riding for: Over 20 years  I ride: Every day  I would class myself as: Expert

I regularly do the following types of riding: time trialling, commuting, club rides, sportives, fixed/singlespeed,

As part of the tech team here at F-At Digital, senior product reviewer Stu spends the majority of his time writing in-depth reviews for, and ebiketips using the knowledge gained from testing over 1,500 pieces of kit (plus 100's of bikes) since starting out as a freelancer back in 2009. After first throwing his leg over a race bike back in 2000, Stu's ridden more than 170,000 miles on road, time-trial, track, and gravel bikes, and while he's put his racing days behind him, he still likes to smash the pedals rather than take things easy. With a background in design and engineering, he has an obsession with how things are developed and manufactured, has a borderline fetish for handbuilt metal frames and finds a rim braked road bike very aesthetically pleasing!

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Off the back | 8 months ago

Cuirious as to why this is branded as Trek and not Bontrager. The Bontrager Ballista was quite a good helmet but the pads were terrible. Hope this ones are better, especially on the brow. 


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