It has been three decades since wearing a helmet while road biking in the US became more or less mandatory. Naturally, being safety conscious, we are all in favor of wearing a helmet any time your hindquarters touch your saddle. 

However, when it is time to buy your first helmet or upgrade from your old one, the choices can seem endless, with every company boasting its own safety features and laundry list of proprietary technologies. Naturally, they all claim that theirs is the best. 

To help cut through this noise, our review of the best road bike helmets of 2021 will help you choose the best road bike helmet for your wants and needs, be they focused on safety, weight, comfort, ventilation, aerodynamics, value, or some combination of these factors.

How Do Road Bike Helmets Work?

Road bike helmets function similarly to mountain bike, and other two-wheel, extreme sport oriented helmets. Generally, they are comprised of two layers: an outer, polycarbonate layer, and an inner layer made of eps foam. The hard plastic outer layer protects the eps foam and allows the helmet to skid, rather than catching and whipping your neck around. Meanwhile, in the event of a hard impact, the eps foam will crush and/or break, absorbing some of the force of the impact. This force absorption is the main way that helmets protect your brain. Some road bike helmets replace the eps foam with more dense epp foam. Epp foam will typically stand up to more impacts before crushing, but this means that your head will absorb more of the force of those impacts.

Additionally, this all means that a good helmet is designed to save your head exactly once. If you took a fall that left you concussed, or left your helmet dented in any way, then it is pretty safe to assume that its impact absorbing abilities have been compromised and that it should be replaced.

MIPS and Other Anti Rotational Features

MIPS, or other companies’ proprietary takes on anti-rotational impact features are now pretty standard across the board in high-end road bike helmets, and these features are even making their way down the line to mid and budget tier helmets. 

The idea behind MIPS was that traditional helmets did a great job of protecting heads and brains from direct, straight on impacts, but in reality, this is not the nature of most crashes. Most often, a helmet contacts the ground or another foreign object at an angle, creating a rotational force on the helmet, and by extension, your head. MIPS aims to solve this problem.

The standard MIPS system consists of a smooth, plastic insert, which is attached to the helmet via small, plastic pegs. When a strong rotational force is exerted on the helmet, these pegs sheer away, allowing the helmet to rotate without whipping the head and neck with it.

What To Look For In A Road Bike Helmet And How We Rated

When it is time to buy a new road bike helmet, there are a few things to consider, and we based our review of each helmet on these factors.

First and foremost, it is important to find a helmet that fits your head. Safety testing for helmets is done on crash test dummies, with the helmets cinched down much more tightly than they will be on your head. This means that having a proper fitting lid is essential for getting the maximum amount of protection for your head. While fit will vary from person to person, some brands tend to fit certain head shapes better, and some helmets offer a better system of adjustment, allowing for a good fit with a broader range of head sizes and shapes.

Just behind fit, are weight and ventilation. Roadies tend to be a particularly weight conscious group, and a helmet is a place where you can often shave off a few grams. Meanwhile, ventilation will be extremely important for riders who live in hot or humid areas, and less so for those living in more temperate climates. As a general rule, higher end helmets tend to be lighter and better ventilated.

We also judged the road bike helmets that we reviewed based on any additional features that they offered, be these safety-related or quality of life-related. At this point, we don’t make too much fuss over helmets having MIPS, because it is more common than not. Instead, we will save this attention for helmets that chose to forgo MIPS, and for those that employ a proprietary technology that we have not already talked to death.

Finally, aerodynamics is another feature of the best road bike helmets, and it is one that can help save you a couple of wasted watts over the course of a long day. While we don’t have a wind tunnel at our disposal, we break down the manufacturers’ claims of aerodynamics, as well as how the helmets actually feel while riding.

The Best Road Bike Helmets of 2021: Cycling Helmet Review

The Best of The Rest

Kask Valegro

Kask Protone

Bell Z20 MIPS

Kask Mojito X

POC Ventral Spin

Best Road Bike Helmet of 2021

The POC Ventral Spin is another innovative helmet from POC with high ambitions that blew us away. We feel that it represents the best combination of safety, aerodynamics, comfort/adjustability, and ventilation on the market, and it is fairly lightweight to boot. All in all, we think the POC Ventral Race Spin is the best all-around road bike helmet on the market for serious racers. We put the qualifier, “for serious racers” because there had to be a downside, and that downside is price. The POC Ventral Spin retails for $290 and because it is so new, it is difficult to find below this price. A better value can be found in the Giro Synthe, but for racers who want the best and aren’t afraid of breaking the bank, the POC Ventral Spin is our top pick.

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Giro Synthe MIPS

Best All Around Premium Road Bike Helmet of 2021

The Giro Synthe is a premium road bike helmet aimed at bringing all of the features that you want in a race day helmet to a helmet that is comfortable enough to be worn every time you throw a leg over your bike. While this might sound like a tall task, the Giro Synthe MIPS road bike helmet lives up to its rather lofty ambitions in almost every way.

In terms of weight, ventilation, aerodynamics, and safety, the Giro Synthe goes blow to blow with the POC Ventral Spin, even coming out ahead in a few areas. Meanwhile, it can be found significantly cheaper than the POC Ventral Spin, although their MSRPs are quite similar.

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Lazer Z-1 MIPS

1B Pick for Best All Around Premium Road Bike Helmet of 2021

The Lazer Z-1 MIPS is a true contender among the crowded lineup of premium road bike helmets that we reviewed. Its safety, ventilation, comfort, and adjustability are all top notch. Meanwhile, it offers some of the most unique features and styling of any helmet that we reviewed. In the end, we would basically call it a push between the Lazer Z-1 MIPS and the Giro Synthe for the best overall road bike helmet in the sub $250 price range. Like the Synthe, the  Lazer Z-1 MIPS retails for just over $250, but sale prices can be found for under $180. While the Synthe is lighter and a bit more aerodynamic, the ARS retention system and unique features of the Lazer Z-1 MIPS will undoubtedly speak to many cyclists.

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Giro Aether

Top Pick for Safety at the Risk of Breaking the Bank

The Giro Aether is a helmet that is impressive in just about every way. It is fairly light, extremely well ventilated, more aerodynamic than some helmets designed with aerodynamics as a priority, it features one of the best fit systems on the market, and its MIPS spherical safety technology is among the most innovative helmet features that we have ever seen. The only downside that we can see to the Giro Aether is its whopping price tag, which will put it out of reach for many cyclists.

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Smith Trace MIPS

Another Top Pick For Safety

If you are looking for a helmet that goes all in on safety technology, then a Smith helmet will rarely steer you wrong and the Smith Trace MIPS road bike helmet is a perfect example of that. It certainly makes a few sacrifices to achieve its lofty goal of pushing the boundaries of helmet safety, but we think they are well worth it. At $250, the Smith Trace MIPS is right in line with other top of the line helmets from a pricing perspective. If you want maximum protection and don’t mind a helmet that is a bit warmer than the competition, then the Smith Trace might be the best road bike helmet for you.

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Giro Foray MIPS

Best Road Bike Helmet For Cyclists on a Budget

Price: $84.95 

Weight: 298g

Vents: 21

Fit System: Roc Loc 5

Safety Tech: MIPS

What We Like: Premium Features at a Budget Price

What We Don’t: Doesn’t Vent or Fit Quite Like the Giro Synthe

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Bell Stratus MIPS

The Bell Stratus MIPS road bike helmet is Bell’s second-tier offering, behind the premium Z20 MIPS. While the Giro Synthe and Bell Z20 might do everything the Stratus does a bit better, the Stratus does almost everything that they do quite a bit cheaper. And when you consider the fact that the Bell Stratus, which retails for $149.95 can be found on sale as low as $90, you would be hard pressed to find a road bike helmet that offers a better bang for your buck.

The Shimano Saint MX80 is a bit long in the tooth. Hopefully, this Bombproof pedal will get a facelift in the not so distant future, and live up our expectations of what a Shimano mountain bike pedal should be.

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The Best Of The Rest

Kask Valegro

Price: $187.46

Weight: 234g

Vents: 37

Fit System: Octo Fit

Safety Tech: In Molding, MIT

What We Like: Lightweight, Great Ventilation

What We Don’t: No MIPS, Issues With Octo Fit Retention System

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Kask Protone

At $225, the Kask Protone is on the lower end of the price range for premium road bike helmets, however, this price means that it competes against the likes of the Giro Synthe MIPS and Lazer Z1 MIPS, both of which equal or best the Protone in most categories and also offer MIPS. Still, the Kask Protone has a great range of adjustability, solid aerodynamics, and well above average comfort at a not quite outrageous price, which will make it an attractive choice for cyclists who are not concerned with MIPS.

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Bell Z20 MIPS

Price: $138-$229.95

Weight: 305g

Vents: 18

Fit System: Float Fit Race 

Safety Tech: MIPS

What We Like: Float Fit Race Retention System, Ventilation

What We Don’t: Weight, Nowhere to Stash Sunglasses

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Kask Mojito X

The Kask Mojito X is a solid all-around helmet road bike helmet for cyclists who love the fit and finish of Kask helmets but who don’t want to shell out the money for the Protone. The Mojito X does virtually everything well. However, it seems to have more in common with helmets from other brands that come in well below its price point. Given that we take a safety-first approach to helmets, the lack of MIPS in a $200 helmet is a black eye, especially considering that MIPS can be found in the Giro Foray for only $85. In the end, we think the Kask Mojito X is a lot like that expensive Italian suit. It might look great at parties, but there are much better options for the money.

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