how to choose the right helmet ?
how to choose the right helmet ?

For you and your child, the important thing is to choose a bicycle helmet that is adapted to your practice and in which you feel comfortable!

Like any road user, the bike rider takes risks on his bike. It is therefore highly recommended to use a bike helmet for each trip, short or long, on the road or dirt path, in a leisure or sporty version. The question is: how to choose the bike helmet that best suits your needs ?

Choose a bicycle helmet adapted to your practice

There are as many helmets as different kind of practice. A road bike helmet will be different from a mountain bike helmet or an urban bike helmet.

Which helmet for sport bike sessions?  

Mountain biking :
Mountain bike helmets reach a wide audience, with great disparities in levels. You will find it at all prices. However, they all have ventilations, are in a sporty form and are very lightweight for a comfortable and safe sport practice. Some more efficient helmets, such as the SLATE, have an anti-insect net and a visor that make them specific for sports.

Road / Race biking : 
Road bike helmets also have vents to ventilate the cyclist's head and prevent over perspiration. With its elongated and aerodynamic shape reducing wind resistance, the road bike helmets will also be very light and will benefit from the best materials.

BMX : 
Since BMX practice is not about top speed or endurance, it is not necessary to have ventilation or aerodynamic shape. The BMX helmets must be effective in terms of safety, practical to wear and must show a real sign of belonging. The emblematic shape is the timeless bowl shape.

Which helmet for leisure cycling? 

City: to move around your city by bike, it is recommended to have a well covering helmet with less ventilation but a better protection level. You have to be careful of what is around you, but must of all you need to be seen. To be visible biking on the road, choose a helmet that help you be so: with a colorful design, reflective parts, lights integrated to the helmet…

All-Roads : for those willing to enjoy pedaling on various kind of paths, accessibility and comfort are the most important factors. Then you will choose an accessible, versatile and ventilated helmet, such as the PRISM.

Electric bike: the effort is less important for the bike-user, however the speed is much more important, so is the risk. You can therefore prefer a full helmet with few ventilations, covering the head very well, and maybe with a visor such as the QUARTZ VISOR, that will prevent wind and bugs from hurting your eyes.

Whatever your level of cycling, the choice of your helmet is closely linked to your practice. It will define the appearance, the shape of the helmet but also and above all the technologies and materials used.

Choose the right helmet size to be well protected :

Choosing the right bike helmet for your activity is a good start, but it will only provide effective protection if it is adapted to the size of the user. This is why you need to determine what your helmet size is.

Measure your head :

You only need one flexible meter and go around from the middle of the forehead through the occipital hump.

Convert your size:

Helmet sizes are often displayed in centimeters. However, for some brands you will find S / M / L sizes. Note that 52-55cm is a size S, 56-58cm a size M and 59-62cm a size L.

XS sizes are used for children's bike helmets, and for people with a head over 62cm there are also helmets in size XL.


Bicycle helmets also have adjustment elements such as wheels or foam sets that allow the helmet to be optimally adjusted to the bike rider’s morphology.

To ensure optimal protection, the bike helmet must fit perfectly and should not move on the head.

Are the helmet materials important for safety?

A bicycle helmet is composed of several elements that optimize safety, bike rider comfort and aesthetics.

The inner shell :

This is the most impact-resistant part. It can be made of different materials and is designed to absorb the most important shocks. is therefore important to look carefully at the inner material and see if it is suitable for your practice and your budget. For an effective but basic protection, without being in search of comfort or performance, the simple polystyrene shell will be perfect. For a more resistant helmet, you can choose Nylon, Kevlar or aramid, which will be covered by polystyrene.

Finally, for bike riders looking for the best quality in terms of rigidity, comfort and lightness, a carbon shell will be perfectly adapted to your requirements, it is the best technology on the market but it is of course more expensive.

The outer shell:

Designed to resist light impacts, it is located on the outside of the bike helmet and protects the rider from scratches and light impacts. It is composed of a PVC, ABS or Polycarbonate plate. PVC will be perfect for a leisure practice. An outer shell made of polycarbonate will be much lighter and stronger, but will also have a longer life, which justifies its higher price.

The outer overlayer:

This is a thin layer of PVC or polymer applied over the outer shell. Its purpose is to affix decorations and stylish elements to your bicycle helmet.

Other comfort and safety features:

These are the different attachment straps, tightening buckles and closures that allow the bike helmet to be held securely on the head. Without these retaining elements, the protective function of the helmet cannot be ensured. Interior foams are often present inside the helmet to improve comfort when wearing it.

Specific technologies optimize the helmet's protection function :

Within bicycle helmets there are different types of "shock handling" and "performance" technologies, all effective, adapted to each practice and budget. All these technologies can also be found in Cairn bike helmets. 

In Mold:

 The In-Mold technology provides a lightweight and durable bicycle helmet. It consists of an inseparable double layer that distributes the shock over the entire absorption surface.


The Aero Flow Channel is a special ventilation system, directly dug into the EPS of the helmet, providing more natural ventilation that allows you to have a protective and ultra-light helmet! Perfect for road cycling but also for mountain biking.



The Occipital Protect Zone is a specific Cairn technology bringing more protection to the back of your head. It adds a reinforcement at the back of the head to protect the neck of bike riders. This construction is also ideal for the safety of young bike riders. 
In yellow: The Occipital Protect Zone.

In addition, do not hesitate to ask for the advice of a professional when making your purchase. The bicycle helmet is an essential element of protection and safety; Take the time to make the right choice!

Cairn bicycle helmets have additional protective elements ? The Cairn's Advantages :

Flash Light Security:

This Cairn innovation, placed on all urban bicycle helmets, is a removable light placed at the back of the helmet. Thanks to its adhesive strip, the light can be moved directly on your bike or on your other bike gear.

Reflective system:

System made up of reflective stickers positioned at strategic points allowing a high visibility and therefore more safety during your bike sessions at nightfall. It is a must-have on all Cairn bike helmets for children and kids.

Label Protect System:

Cairn being one of the references in terms of safety, the brand has launched its own helmet safety label going beyond the regulations in force.

Wheel Fit:

Cairn Wheel Fit System allows you to adjust the helmet tightness to the nearest millimeter for perfect head support in all circumstances.

Does my child also need a bicycle helmet?

Sometimes ignored by young people, and debated by adults, the use of bicycle helmets is very often controversial. But since March 22, 2017, bike helmets have become mandatory for children up to 12 years old.

Manufacturers of bike gear now offer helmets specifically designed and manufactured for children, which will protect these young adventurers on all roads.

Cairn Easy Clip innovation:

Easy Clip is a technology that locks the helmet safely without pinching the skin with additional comfort foam.

The Cairn Fidlock magnetic loop:

The magnetic loop is magnetically clipped thanks to a magnetic clamping system that is easy to use and very reliable.

A specific size-set dedicated to young bike riders, age-appropriate decorations, personalized technologies: young riders are at the heart of Cairn brand concerns.




Thanks to various innovations that improve comfort and performance, bike helmets are nowadays specialized to be perfectly adapted to the different practices offered by all bike ranges.

At the same time, the helmet is becoming more and more popular and is reaching more and more people, even occasional ones. Whether for children or adults, in the city or in nature, it is protection and safety first and foremost!

Helmet use is and will always be an important safety feature for the bike rider, but it will not prevent accidents. The best way to be safe is to be vigilant and to have good practices on the road. We invite you to read our article on this topic.

Designed in France

Quality control

European standards