The Best Road Bike Helmets

Best Overall Road Bike Helmet

Giro Synthe MIPS

The Giro Synthe MIPS earns high scores in nearly every evaluation metric and has the highest overall score of the helmets tested. It was our testers' favorite helmet and received our Editors' Choice Award. The Giro Aeon was the former Editors' Choice Award winner, and Giro has stepped it up again with the Synthe model. Class-leading comfort, scant weight, and a semi-aerodynamic shell put it at the top. It is heavier than the Aeon but has improved aerodynamics and includes a MIPS liner for better 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 a crash but requires extra care during storage and transport. The Synthe is a high-performance training and racing helmet that won't let you down.

Read review: Giro Synthe MIPS

Best Buy Award

Specialized Airnet MIPS

The Specialized Airnet MIPS is not the cheapest helmet tested, but it offers the most bang for the buck. Its performance-to-value ratio is best-in-test, with all the features you would find in a $300+ helmet for nearly half the price. Generally, as price goes down, looks and design features decrease. 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 you would be hard pressed to guess that it is half the price of competitors. MIPS protection, impressive aesthetics, and two sets of padding (one with an integrated soft visor) set the Airnet apart. On top of that, it is the best-ventilated helmet tested. Our only complaint is its weight, which scored markedly lower than the competition. Despite the weight penalty, it is one of the most comfortable helmets tested.

Read review: Specialized Airnet MIPS

Top Pick Aero Road Bike Helmet

Bontrager Ballista

The Bontrager Ballista has an aerodynamic profile, designed to reduce drag for efficiency and speed. Aero helmets have become popular in the world of professional cycling, and amateur cyclists also enjoy the reduced wind drag they offer. The downside to a 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 we were wearing it. The looks of aero helmets can polarize, but the Ballista stands out for the right reasons. No one will mistake it for a traditional helmet. 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 of what an aero helmet offers.

Read review: Bontrager Ballista

Analysis and Test Results

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


To bring you the best review of helmets for road biking, we purchased the fourteen highest rated and most popular models on the market and put them through miles of asphalt riding and specific tests for three months. All of the helmets we tested meet the same safety standards set by the US Government, but the construction they employ can vary from manufacturer to manufacturer. Below, we discuss each metric we used to assess each model, as well as highlight top notch performers in each category.

Comfort

Road cyclists often spend long periods riding, for both training and racing. A comfortable 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 individual and varies from rider to rider. Despite having different shaped heads, our testers 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 factor in comfort. A comfortable helmet can adapt to a wide range of head shapes.


Our testing revealed that padding, circumferential adjustment design, and chinstrap design had the greatest impact on comfort. Quality padding is crucial, especially in the forehead and temple, because the size adjustment mechanism of most road helmets tightens in the back, which pushes the head to 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 well engineered EPS foam made 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 adjustment to fit various head shapes. 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 near the temple. The Giro Synthe's adjustment system wraps completely around the head, decreasing pressure points and keeping the forehead from being forced into the pads. The Synthe design creates even pressure around the head.


Chinstraps also play a significant role in comfort. Our testers preferred helmets that incorporated thin webbing straps and a Y-buckle, allowing the straps to lie flat. 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.

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 adjustment system design prevents 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 bacteria growth while eliminating odor. Both helmets have thin, pliable webbing straps that lay flat, reducing the potential for chafing and decreasing 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 more uncomfortable the deeper we got into a ride.

Adjustability

A helmet must fit well to function as designed. When helmets are tested by the CPSC, they are fitted to a dummy head and are attached tightly - tighter than the average consumer wears their helmet. For a helmet to protect you, it must stay on your head. A properly adjusted chinstrap and correct fore/aft positioning will ensure your helmet works as designed. The chin strap 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, providing even tension between the front and rear strap. Our favorite helmets feature an adjustable buckle, like 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 helmet's adjustability. We found the non-adjustable buckles to be a deterrent to a 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 broad range of people well while maintaining 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. A non-fixed webbing strap design allows for greater adjustability.


Circumferential tension is achieved by a 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 on the medium-sized helmets we tested falls in the 52-60cm range, with most models offering 4cm of adjustment. The design of the internal harness varies between manufacturers to helmets. All of the helmets we tested use a dial to change tension. The dial works like a ratchet, providing precise tension adjustment. All of the dial adjustments on the helmets we tested functioned as intended.

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


Fore and aft helmet positioning is another important factor for good fit. Every helmet we tested offers fore and aft adjustment, with a 2-5cm range. 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. 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 an 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 Bell Gage offers the best overall adjustability of any helmet 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. The Bell Gage also has two cm of accessible fore/aft adjustment. The Bontrager Ballista is also a standout product, with similar adjustability to the Bell Gage. Its fore/aft adjustment is a bit harder to manipulate. The Kask Protone is the lowest scoring product, because you can't lock the fore/aft adjustment.

Weight

Helmet weight is important. Road cycling is a gram-conscious sport; both pro and amateur riders go to great lengths to decrease weight. Bike technology has progressed, and 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 worn by the rider, like shoes and helmets. Every extra gram slows you down on climbs, and a heavy helmet can also cause 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. 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 increases durability. Second, many of the higher priced helmets we tested include a MIPS liner for protection. The MIPS liner increases the weight by 20-30g. We feel that the modest increase in weight for a MIPS liner is outweighed by the potential safety increase. Intended use and design can also impact helmet weight. Aero helmets are disadvantaged because they have fewer vents with more EPS and polycarbonate material, increasing weight.


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 low weight with lots of vents and no MIPS liner, while the Synthe has fewer vents and a MIPS liner. Other high scoring products include the affordable Giro Savant and, somewhat surprisingly, the aero Bontrager Ballista. Neither of these helmets has a MIPS liner, which helps to decrease weight.

Looks and Design

The aesthetic appeal of a helmet is 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 cycling. Many of the helmets we tested have design features not taken into account in our other rating metrics. This is where we give helmets credit for features like 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 looks like a traditional cycling cap worn under the helmet. This feature helps to keep the sun out of our eyes and deflects rain from sunglasses on a wet ride. Also, the Airnet has rubber sunglass grippers on the front and rear vents to provide a secure, convenient storage option for glasses during long climbs.

The Smith Overtake also scores high, due to the use of 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 accommodates storage of the Smith sunglasses on top of the helmet.

Ventilation

Ventilation is our most heavily weighted category. A well-ventilated helmet keeps your head and core temperature down, enhancing performance. Good ventilation also keeps sweat out of your eyes. As aerodynamics become a higher priority for manufacturers, balancing ventilation with aerodynamics 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 airflow over the head. Full aero helmets, such as the Bell Star Pro and the POC Octal Aero, are at a disadvantage, as they have 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 that kept our heads cool on hot climbs when we were crawling along. On some helmets, the MIPS liner can block helmet vents, but that is not an issue with the Airnet. The MIPS liner aligns 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 with only seven vents, 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 allow for passive heat escape, but their orientation makes the vast majority of tubes sit perpendicular to the wind path, and they let in little air.

Durability

Many manufacturers choose weight savings over durability in road helmets. EPS foam is relatively soft, prone to dents, and easily abraded. The most durable road helmets have a polycarbonate shell that extends down, wrapping the base of the EPS shell. Helmets that have a full-wrap shell get banged up less during 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 a crash impact. So our assessment of durability is a measure of the helmet's ability to stand daily abuse, wear, and accidental travel bumps and scrapes.


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 wraparound polycarbonate shell that protects the helmet base but has more EPS foam exposed on the upper portion than the Overtake.

Conclusion

The primary purpose of a road bike helmet is to protect your head in a crash. All helmets sold in the USA are subjected to the same safety standards, but manufacturers design helmets to achieve objectives beyond the primary function of safety. Helmets may offer the same level of protection, but they are not all created equal. Ventilation, comfort, and adjustability enhance or detract from the quality and overall satisfaction your helmet will bring you. 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 scoring. For more assistance choosing the right helmet for your needs, see our Buying Advice Article.