The Best Road Bike Helmet Review

Thousands of miles were put in on the road during the Road Bike Helmet Review.
Road bike helmets are a critical piece of safety gear for any cyclist. What combination of features and factors equate to being a high-quality helmet? What is the difference between a top of the line helmet and an entry-level model? Does a higher price equal more safety? What is MIPS? We took 14 of the most popular, well-regarded road helmets and put them through hundreds of hours of head-to-head testing to provide you with the answers you need. Each product has been rated in six performance-based metrics, including Comfort, Adjustability, Weight, Looks and Design, Ventilation, and Durability. If you are looking for a new helmet, then read on for the most comprehensive head-to-head testing and evaluation available.

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Test Results and Ratings

Displaying 1 - 5 of 14 << Previous | View All | Next >>

Analysis and Award Winners

Review by:

Senior Review Editor

Last Updated:
February 17, 2017

Best Overall Road Bike Helmet

Giro Synthe MIPS

Giro Synthe Mips Editors' Choice Award

Price:   Varies from $189 - $270 online
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The Giro Synthe MIPS earned high scores in nearly all of our evaluation metrics and has the highest overall score of the 14 helmets we tested. It was by far our testers' favorite helmet and has earned our Editors Choice Award. The Giro Aeon was the former winner of our Editors Choice Award, and Giro has stepped it up again with the Synthe model. Class-leading comfort, low weight, and a semi-aerodynamic shell has elevated it to the top of the charts. It is heavier than the Aeon, but has improved aerodynamics and also includes a MIPS liner for improved protection. The only flaw in the Synthe is exposed EPS foam on the lower portion of the helmet brim, which is prone to damage if dropped or scraped. This does not increase the likelihood of damage in the event of crash, but requires a bit of extra care during storage and transport. The Synthe is a high-performance training and racing helmet that won't let you down.

Top Pick Aero Road Bike Helmet

Bontrager Ballista

Bontrager Ballista Top Pick Award

Price:   $175 List

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No MIPS or sunglass storage
The Bontrager Ballista is a road bike helmet with an aerodynamic profile, designed to reduce wind drag for optimum efficiency and speed. Aero helmets have become increasingly popular in the world of professional cycling, and amateur cyclists have also discovered the benefit of reduced wind drag. The downside to a slippery fast helmet is poor ventilation. The Ballista was by far the best-ventilated and most comfortable aero helmet we tested, and for this, it wins our Top Pick award. With plush AgIon Fit padding, well-placed vents, and extensive internal channeling, we often forgot that we were wearing an aero helmet. The looks of aero helmets can be polarizing, but the Ballista stands out for the right reasons. No one will mistake it for a traditional helmet, but it looks sleek and fast, with an elongated shape rather than the round bowling ball look of other aero helmets. The Ballista is the aero helmet for the skeptic, it changed our opinion on what an aero helmet can offer.

Best Buy Award

Specialized Airnet MIPS

Specialized Airnet MIPS Best Buy Award

Price:   $170 List

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Decent Ventilation
Classic Look
The Specialized Airnet MIPS is not the cheapest helmet we tested, but it offers the most bang for the buck. Its performance to value ratio is the best in test. It has all of the features you would find in a $300+ helmet, and is nearly half the price. As price goes down, the looks and design features generally follow. This is not the case with the Airnet. Your riding buddies will think you picked up the latest super helmet when you show up to the group ride in it. It looks the part of a pure racing lid, and wearing it you would be hard pressed to notice that it is half the price of competing helmets. MIPS protection, awesome aesthetics, and two sets of padding (one with an awesome integrated soft visor) set the Airnet apart from the competition. On top of that, it is the best-ventilated helmet we tested. Our only complaint is the weight, where it scored markedly lower than the competition. Despite the weight penalty, it is one of the most comfortable helmets we tested.

Analysis and Test Results

A road bike helmet is the only thing between your head and the pavement when you go down on the bike. Those who have been riding on the road long enough know that it is not a matter of if - but when - we will go down. Investing in a good helmet should be your main priority when it comes to cycling accessory purchases. All of the helmets we tested meet the same safety standards set by the US Government, but the construction they employ to meet those standards can vary from manufacturer to manufacturer.

Other non-mandated safety features, such as MIPS, are also used in some helmets. There are three primary types of road bike helmets on the market: traditional, semi-aero, and aero helmets. In addition, many companies also offer time trial helmets, which are used in time trials and triathlons. We cover the differences in helmet types below, as well as applicable safety standards. For more help deciding which helmet is right for you, see our Buying Advice Article.

The chart above highlights our entire fleet and the order in which all competitors finished overall.

Bicycle helmets are designed for a single impact. When a crash occurs, the foam in the helmet is designed to crush and compress to absorb energy. Once the foam has been compressed it no longer offers the same level of impact protection. If you crash and impact your helmet, it should be replaced. Some helmets have an internal skeleton within the EPS foam to prevent the helmet from breaking into multiple pieces. While no data on the effectiveness of the feature could be found, we find it logical to think that the helmet remaining intact following the initial impact could potentially protect the head from a secondary impact; think of a tumbling fall.

To read more about safety standards, MIPS, and types of road bike helmets, continue reading in our buying advice.

Criteria For Evaluation


Road cyclists often spend long periods on the bike, for both training and racing. A comfortable road helmet is critical due to the amount of time you will be wearing it. Ideally, you will not be thinking about your helmet while riding; it should essentially disappear once you put it on. Head shape is an individual characteristic and varies from rider to rider. We found during our evaluation that despite having different shaped heads, our testers universally rated the same helmets highly for comfort. In contrast, during our full-face helmet review, we found the shape of a rider's head to be a greater factor in relation to comfort. A comfortable helmet has the ability to adapt to a wide range of head shapes through adjustments.

Our testing revealed that padding, circumferential adjustment design, and chinstrap design had the greatest impact on comfort during testing. Good quality padding is crucial, especially at the forehead and temple area, because the size adjustment mechanism of most road helmets tightens in the back, which pushes the head forward into the front of the helmet. The helmets with the thickest, densest padding were not necessarily the most comfortable - rather the interface between the pads, the helmet adjustment system, and the EPS foam being well-engineered make the biggest difference. The Kask Protone is a good example; it has the thickest, most luxurious pads of any helmet we tested, yet the minimally padded Giro Synthe outscores it.

All of the helmets we tested have an internal adjustment system that allows the helmet to be adjusted to fit heads of varying sizes. We determined that the best design was one that makes a complete loop around the head. Most helmets we tested use a system that is anchored to the shell of the helmet somewhere near the temple. The Giro Synthe adjustment system wraps completely around the head, which decreases pressure points, and does not force the forehead into the pads. The Synthe design creates even pressure all the way around the head.

The Giro Synthe MIPS is equipped with a MIPS liner and the awesome Roc Loc Air Adjustment System.  Our only complaint is the exposed EPS foam around the base.
The Giro Synthe MIPS is equipped with a MIPS liner and the awesome Roc Loc Air Adjustment System. Our only complaint is the exposed EPS foam around the base.

Chinstraps also play a big role in comfort. Our testers preferred helmets that incorporate thin webbing straps, and a Y-buckle that allows the straps to lie flat against the skin. The Specialized Airnet and Giro Synthe use different designs, but are both standouts with thin supple webbing and well-designed Y-buckles that allow the webbing to lie flat against the skin.

The Giro Synthe and the Lazer Z-1 MIPS are standouts for comfort, both scoring a perfect 10. Both helmets have minimal padding, but the design of the adjustment systems prevent pressure points by being circumferential on the Giro Synthe, and nearly circumferential on the Lazer Z-1. The Synthe and the Z-1 both have pads made of X-Static material, which has silver incorporated into the fabric to prevent the growth of bacteria and eliminate odor. Both helmets also have very thin pliable webbing straps that lay flat against the face, which reduces the potential for chafing and decreases wind noise. The lowest scoring helmet for comfort is the Kask Protone. Despite its generous padding, the adjustment system creates pressure points at the front and back of the head, making it increasingly more uncomfortable the deeper we got into a ride.

The Y-buckles on the Lazer Z-1 MIPS are simple and easy to adjust.
The Y-buckles on the Lazer Z-1 MIPS are simple and easy to adjust.


A helmet must fit well in order to function as it is designed. When helmets are tested by the CPSC, they are fitted to a dummy head and are attached very tightly - tighter than the average consumer wears their helmet. In order for a helmet to protect you in a crash, it must stay on your head. A properly adjusted chinstrap, and correct fore/aft positioning will ensure your helmet works as designed. The chinstrap should be tight, but not so tight that it is choking you. The helmet should be positioned so that it sits squarely on your head, not tilted back.

All of the helmets we tested have a strap system with one strap behind the ear and one in front. The straps come together below the ear, and are joined by a plastic Y-buckle. The webbing straps can in most cases be adjusted at the Y-buckle to provide even tension between the front and rear strap. Our favorite helmets feature an adjustable buckle, such as the Giro Synthe and the Bell Gage. Some helmets we tested, like the Kask Protone and the Specialized Airnet have non-adjustable Y-buckles. A non-adjustable Y-buckle reduces the adjustability of the helmet. We found the non-adjustable buckles to be a detriment to good fit, but this did not play out equally amongst the helmets.

The Specialized Airnet, despite its lack of an adjustable Y-buckle, has an uncanny ability to fit a wide range of people very well and maintain equal tension on the front and rear straps. The Kask Protone is the opposite - the lack of adjustability was a deal breaker for some testers who could not achieve equal tension on the straps. Some of the helmets we tested, such as the Bell Gage, allow the user to center the chinstrap buckle by feeding webbing through the rear strap attachment point. Other helmets like the Giro Synthe and the Specialized Airnet have fixed webbing attachment points which do not allow for chin strap buckle adjustment from side to side. We prefer a non-fixed webbing strap design, as it allows for greater adjustability.

The small  yet secure and comfortable chin strap buckle on the Giro Synthe MIPS.
The small, yet secure and comfortable chin strap buckle on the Giro Synthe MIPS.

Circumferential tension is achieved with some sort of dial-like mechanism at the back of the helmet, or in the case of the Lazer Z-1, at the top of the helmet. Adjustment range on the medium-sized helmets we tested falls in the 52-60cm range, with most models offering 4cm of adjustment. The design on the internal harness varies by manufacturer and helmet model. All of the helmets we tested use a dial mechanism to increase or decrease tension. The dial works like a ratchet, providing very precise adjustment of tension. All of the dial adjustment devices on the helmets we tested functioned as intended.

Some are smaller than others, such as the very small dial on the Giro Synthe, which can be difficult to feel with very thick gloves. The Lazer Z-1 has a dial mechanism on top of the helmet that can also be hard to feel with gloves on. Our favorite dial mechanisms are exposed 360 degrees and are large enough to be easy to adjust while wearing gloves, such as the dial on the Smith Overtake. Other tensioning systems exist and are employed on some of the mountain bike helmets we have previously tested, but we prefer and recommend a dial mechanism as it allows for easy one-handed adjustment of the helmet tension while riding.

The circumferential adjustment dial on the Giro Synthe MIPS is small  but still easy to manipulate with gloves on.
The circumferential adjustment dial on the Giro Synthe MIPS is small, but still easy to manipulate with gloves on.

Fore and aft positioning of the helmet is another important factor in achieving a good fit. Every helmet we tested offers fore and aft adjustment, with a range 2-5cm. The Kask Protone has the greatest degree of adjustment at 5cm, but scores poorly here, because the mechanism that locks the internal harness in place at the rider's preferred fore/aft position slips easily and does not stay in place. None of the fore/aft adjustment mechanisms are particularly easy to adjust, but once set, they should stay in place to provide a safe fit. Some of the adjustment devices are buried under the MIPS liner, making adjustment even more difficult; this is the case with the Lazer Z-1. We prefer an exposed adjuster, seen on models such as the Giro Synthe and the Bell Gage.

The Giro Savant has 2cm of fore and aft adjustment. The rear webbing attachment point is floating  which allows for a wide range of adjustability.
The Giro Savant has 2cm of fore and aft adjustment. The rear webbing attachment point is floating, which allows for a wide range of adjustability.

The Bell Gage offers the best overall adjustability of any helmet we tested, earning it a 9/10. The non-fixed position of the rear strap allows for easy centering of the chinstrap buckle. The tensioning dial is not fully exposed, but is large enough to allow for adjustment with gloves on. The Bell Gage also has 2cm of easily accessed and manipulated fore/aft adjustment. The Bontrager Ballista is also a standout product with similar adjustability to the Bell Gage, but the fore/aft adjustment is a bit more difficult to manipulate. The lowest scoring product is the Kask Protone, due to the inability to lock the fore/aft adjustment mechanism.

The Bell Gage MIPS has a non-fixed rear strap system that provides a lot of adjustment ability.
The Bell Gage MIPS has a non-fixed rear strap system that provides a lot of adjustment ability.


Helmet weight is important. Road cycling is a very gram-conscious sport; both pro and amateur riders go to great lengths to decrease weight. Bike technology has progressed to the point that every professional cyclist is already on a bike that meets the UCI minimum weight limit, so further decreases in grams can only be found in items that are worn by the rider such as shoes and helmets. Every extra gram slows you down on the climbs and a heavy helmet can also cause more neck fatigue on a long ride. While weight can impact comfort, all of the helmets we tested are relatively light.

Interestingly, many of the more expensive helmet models we tested, such as the Lazer Z-1 and the Kask Protone, are heavier than their more affordable counterparts, like the Giro Savant. Several factors account for this phenomenon. First, many of the higher end helmets (such as the Kask Protone) have more polycarbonate shell covering the EPS foam. This marginally increases weight, but greatly increases durability. Second, many of the higher priced helmets we tested include a MIPS liner to increase protection. The MIPS liner increases the weight of a helmet by 20-30g. We feel that the modest increase in weight for a MIPS liner is outweighed by the potential to increase safety. Intended use and design can also impact helmet weight. Aero helmets are at a disadvantage, because they generally have fewer vents with more EPS and polycarbonate material increasing weight.

The Aeon is the lightest helmet we tested at 225g.
The Aeon is the lightest helmet we tested at 225g.

The highest scoring and lightest weight helmet we tested is the Giro Aeon. At 224g, the Aeon is 44g lighter than the Giro Synthe. The Aeon achieves this remarkable low weight with an impressive amount of vents and the omission of a MIPS liner, while the Synthe has less vents and includes a MIPS liner. Other high scoring products include the affordable Giro Savant and, somewhat surprisingly, the aero Bontrager Ballista. Neither of these helmets have a MIPS liner, which helps to decrease weight.

Looks and Design

The aesthetic appeal of a helmet is somewhat subjective because, as they say, beauty is in the eye of the beholder. The look of aero helmets, in particular, is a polarizing topic in the cycling world. Many of the helmets we tested have design features that are not taken into account in our other rating metrics. This is where we give helmets credit for features such as rubber sunglass holders, storage bags and yes, our take on aesthetic appeal.

The Specialized Airnet scores a perfect 10, for its classic look and integrated soft visor. The Airnet comes with two sets of pads, one of which has a built-in soft visor that has the look of a traditional cycling cap worn under the helmet. We love this feature, which helps to keep the sun out of our eyes, and deflects rain away from sunglasses on a wet ride. In addition, the Airnet has rubber sunglass grippers on both the front and rear vents to provide a secure, convenient storage option for glasses during long climbs.

The Smith Overtake also scores highly due to the use of a material called Koroyd in place of thick EPS foam. Koroyd is a honeycomb-like composite structure that Smith claims will absorb impact more effectively than EPS. The Overtake uses EPS, but is able to decrease the thickness of the EPS panels by using Koroyd. The result is a sleek, low profile helmet. The Overtake also has a molded shell that perfectly accommodates storage of the Smith sunglasses on top of the helmet.

The Specialized Airnet MIPS has a classic look  but features like the rubber sunglasses grippers in the vents show that it is anything but old school when it comes to performance.
The Specialized Airnet MIPS has a classic look, but features like the rubber sunglasses grippers in the vents show that it is anything but old school when it comes to performance.


Ventilation is a highly regarded metric and is our most heavily weighted category. A well-ventilated helmet keeps your head cooler and your core temperature down, enhancing performance. Good ventilation also keeps sweat out of your eyes during hard efforts. As aerodynamics have become a higher priority for helmet makers, balancing ventilation with aerodynamic benefit has become a challenge. The best-ventilated helmets are not necessarily those with the most vents, but rather the ones that pair properly-placed vents with internal channeling that allows air to flow over the head. Full aero helmets such as the Bell Star Pro and the POC Octal Aero are at a disadvantage as they have very few vents and tend to be hot, especially at the low speeds often experienced on a steep climb.

The Specialized Airnet is the highest scoring helmet we tested. Air movement and heat evaporation are excellent, thanks to 21 well-placed vents, which kept our heads cool on the hottest climbs when we were barely crawling along. On some helmets, the MIPS liner can block helmet vents, but that is not an issue with the Airnet. The MIPS liner lines up perfectly with the vents and there is no airflow restriction. Another standout helmet is the heavily ventilated Lazer Z-1, with its 31 ventilation openings.

Lower scoring products such as the POC Octal Aero has only 7 vents, and can be stiflingly hot on even moderately warm days. Another surprise was the Smith Overtake, which our testers found to be nearly as hot as the Octal. The Overtake appears to be heavily ventilated, but the hollow Koroyd tubes fill each vent. The Koroyd tubes do allow for passive heat escape, but due to their orientation, the vast majority of the tubes sit perpendicular to the wind path around the helmet, and let in very little air.

Large vents on the back of the Specialized Airnet MIPS help evacuate hot air efficiently.
Large vents on the back of the Specialized Airnet MIPS help evacuate hot air efficiently.


Many manufacturers choose weight savings over durability when it comes to road helmets. EPS foam is relatively soft, prone to dents, and easily abraded. The most durable road helmets we tested have a polycarbonate shell that extends down and wraps the base of the EPS shell. Helmets that have a full wrap shell get less banged up from everyday use because the EPS foam is protected. No matter how well a helmet is constructed, they are truly one hit wonders when it comes to an impact that results from a crash. So our assessment of durability is a measure of the helmets ability to stand up to the abuse of daily wear and accidental bumps and scrapes incurred through travel.

The Smith Overtake earns a perfect 10, with almost no exposed EPS foam on the exterior of the helmet. The polycarbonate shell extends around the base of the helmet and covers nearly the entire upper portion of the helmet. The Specialized Airnet also receives high marks with a wrap-around polycarbonate shell that protects the base of the helmet, but it has much more EPS foam exposed on the upper portion than the Overtake.

The Smith Overtake MIPS has a full wrap polycarbonate shell and a very comfortable set of X-Static pads.
The Smith Overtake MIPS has a full wrap polycarbonate shell and a very comfortable set of X-Static pads.


The Giro Synthe MIPS is a great road helmet and is also our number one pick for cyclocross.
The Giro Synthe MIPS is a great road helmet and is also our number one pick for cyclocross.

The primary purpose of a road bike helmet is to protect your head in the event of a crash. All helmets sold in the USA are subjected to the same safety standards, but manufacturers design helmets to achieve different objectives beyond the primary function of safety. Helmets may offer the same level of protection, but they are not all created equal. Factors such as ventilation, comfort, and adjustability enhance or detract from the quality and overall satisfaction your helmet will bring. The 14 helmets we tested are designed for road use, but are often used for cyclocross, XC mountain bike racing, and gravel riding. Read our individual product reviews to find out all the details behind the scoring. For more assistance with choosing the right helmet for your needs, see our Buying Advice Article.
Curtis Smith
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