Home > Bike Types > Road Bike

Specialized Propero 4 Helmet is Totally Redesigned for Aero Speed + Ventilation

Specialized Propero 4 bike helmet
Support us! Bikerumor may earn a small commission from affiliate links in this article. Learn More

Specialized has a new version of the Propero, but if you’re familiar with the previous versions, you might not even recognize it. Thanks to borrowed design language from the S-Works Evade 3 and Prevail 3, the new Propero 4 looks like an entirely different product – which is a good thing.

Notably, the Propero 4 brings much of the performance of the higher-end S-Works models to a more attainable price point. The $200 Propero 4 isn’t exactly cheap, but it checks in at 2/3rds the cost of the premium models.

When it came time to design the new helmet, Specialized says they started with aerodynamics first. Starting with a battery of CFD tests and multiple helmet shapes, Specialized narrowed it down to two shapes and then took those to their in-house Win Tunnel. This wind tunnel testing with a male road race mannequin validated the Propero 4 as being 4 watts faster than the S-Works Prevail 3. That works out to it being 15 seconds faster over 40km with an average speed of 45kph. Specialized doesn’t state how it compares to the Evade 3 so we’re assuming the Evade 3 is still faster.

To improve ventilation, Specialized again utilized CFD to manage airflow around and through the helmet. In addition, they claim to have created a new way of increasing airflow that they’re calling Micro Channeling. This involves 2mm offset micro channels that are said to create turbulence in the airflow through the helmet to “create a continuous, refreshing flow of air.” Combined with large rear vents, the helmet manages to move a lot of air around and through it.


On top of being aerodynamic and well-ventilated, the Propero 4 puts a focus on safety with MIPS Evolve. The slip plane is attached to flexible anchors which provides the 10-15mm of movement to reduce rotational forces transmitted to the brain during a crash. Outside of MIPS, the helmet also scored the highest 5-Star helmet rating from Virginia Polytechnic Institute and State University.

I’m happy to see that while Specialized went with light weight web splitters, their Tri-Fix splitter still allows adjustment fore and aft.

Actual Weight

On the scale, our medium sample weighs in at 308g.

First Impressions

When it comes to new road helmets, I haven’t had great luck recently – until now. I really wanted to like the Prevail 3, but the revised shape of the helmet digs into the back of my head. Then, on the Lazer Z1 Kineticore, the non-adjustable webbing straps meant the chinstrap was poorly positioned on my head.

Fortunately, the Propero 4 fits me nearly perfectly in all aspects. It’s extremely comfortable, and right out the box the Tri-Fix splitters were in the right position, even though they are adjustable.

In spite of being an aero helmet, the Propero 4 does a great job of making it look like you’re not wearing an aero helmet. In my opinion, it’s an aero helmet that you can wear on a daily basis without feeling like you look like a dork out to set some PRs on the bike path. That’s not to say it’s not aerodynamic though. On a particularly windy ride where everything was getting buffeted by the wind, I felt like my head was uniquely stable – in a way that you could feel.

More importantly to me, it’s incredibly well ventilated. While riding, you can actually feel the airflow coming through the back of the helmet onto your neck. I haven’t tried it on a super hot day yet, but first impressions make me think that it would still be very comfortable.

Pricing & Availability

Specialized Propero 4 bike helmet colors

Offered in five colors, the Propero 4 is priced at $200 and is available now. Helmets will be offered in S, M, and L sizes in both a “classic” and “round” fit.


Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Newest Most Voted
Inline Feedbacks
View all comments
Matt S
Matt S
2 months ago

Interested to hear that the fit worked for you (@Zach) much better with the Propero 4 than the Prevail 3. I also wanted to love the Prevail 3 (the Prevail 2 Vent is my current go-to and fits like a glove), but the sizing and rear strap made it a rather unappealing option (with a very premium price as well). Hopefully I have similar luck with this new lid when it’s time to add a new bucket to the mix.

2 months ago

Still waiting for someone to make the lightest possible MIPS helmet with the best ventilation. I wouldn’t care if it was 10w slower than this and the same price. I just want the ventilation and less weight on my neck.

Subscribe Now

Sign up to receive BikeRumor content direct to your inbox.

Subscribe Now

Sign up to receive BikeRumor content direct to your inbox.