Man riding bike on a trail, wearing a helmet

How to Choose Your Bike Helmet

Your helmet is a safety-must-have, whether you're a city commuter or a mountain biker tackling rugged and rocky terrain; get the right one with our guide below. 

Find some handy tips to help with your cycling and introduce some much-needed safety gear to your commute or passion sport with our guide below. And while a helmet isn’t necessarily a legal requirement in the UK, a helmet can help reduce the risk of serious injuries and is well worth the browse!

How does a Bike Helmet Protect your Head?

Bike helmets generally have similar basic constructions, featuring the following:

• An outer plastic shell
• Inner padded liner (for impact absorption)
• Extra padding (for comfort)
• Air vents
• Adjustable fitting

The hard shell is designed to spread the impact over a greater surface area, minimising the likelihood of a fracture. The soft liner squeezes inward upon impact to absorb the force, so there is an overall decrease in how much impact the crash will have on your head. By combining the protection of the hard shell and padded inner liner, a cycling helmet makes for a great way to prevent and soften potentially serious head injuries.

Choose the Right Bike Helmet

Different riding styles require different levels of protection, so you need a helmet specifically designed for the riding you’ll be engaged in, whether for city, road riding, or mountain terrains. Kids, in more ways than one, are also a whole other ball game. Selecting your helmet is all about finding the perfect fit, and there’s more to it than a snug feel! First of all, consider where you’ll be riding.

Man riding on the street wearing white helmet.

Where are you Riding?

When determining what kind of helmet will suit your riding, it depends on the riding you do. Cycling helmets usually cover the following:

• City
• Countryside
• All-terrain
• Road

Each discipline has helmets optimised to alleviate terrain-specific risks, as the kind of accidents in mountain biking will vary significantly for inner-city commuters.

City Or Hybrid Bike Helmets
City or hybrid bike helmets are more suited to being stored in a basket or on your handlebars as they’re likely to be made from ABS. ABS is a sturdy plastic that adds to the durability and long-term use of the helmet. Certain helmets also have a place for attaching a VIOO Clip, a small light that shows other road users where you are.

Road Bike Helmets
Road bike helmets are lighter, well-ventilated and well-fitting. The very best helmets are the ones that balance all three of these essential criteria. The number of vents is important too, and you’ll probably already know how many you need – or at least how warm you tend to get during a ride.

Mountain Bike Helmets
These helmets have the same characteristics as road cycling helmets. There are, however, a few additional requirements; it needs to cover your whole head to protect you from branches and falls, which are more likely in this discipline. Consider an additional visor to help protect you from mud and keep your vision uninhibited, particularly when cycling through wet terrain.

Kids’ Helmets
Kids helmets include children up to the age of nine – from 10 years old, you can comfortably opt for an adult helmet. Cycling helmets for kids aged one to three are more compact and shorter at the back, which makes them more suitable for child seats. Children riding a balance bike can also use this type of helmet. From ages three to nine, you can opt for adult helmets. We recommend opting for a helmet that offers an adjustment wheel at the back to achieve the best fit that your kids aren’t likely to grow out of too quickly.

How to Measure for a Bike Helmet

Your helmet needs to be the right size for comfort and effectiveness in an accident. Getting the right size isn't rocket science – it's simply about getting the measurements right.

It would be best if you always tried your helmet on before buying it. Everyone's head is different and the type of helmet (longer, rounder, more curved, etc.) will affect how comfortable you feel, especially on longer rides.

So when it comes to measuring for a cycle helmet, your local cycling shop will probably have a measuring device available to make the process a little easier. If you're taking your own measurements, follow the steps below.

1. Measure your circumference: Use fabric tape to wrap the tape around your head. Make sure to position the tape above your eyebrows and your ears, as well as around the largest part of the back of your head.

2. Test helmets: Using the measurements you've gotten in the previous step. Helmets are sized to fit a broad range of measurements into basic sizing categories (XS, S, M L and XL). This means there can be significant differences in the sizing of helmets that fall under the same category. It's a good idea to pop into the store to try them on in person and explore the sizing.

3. Sizing: Refer to the specific product size chart of the helmet you're considering. This is because the size notation can vary depending on country, brand and store. You'll find a rough estimate of the sizing arrangement below, using the head circumference and the sizing this covers. If your circumference falls between two sizes, it's best to go to the store and try both sizes on.

• Extra Small: 47-51cm
• Small: 51-55cm
• Medium: 55-59cm
• Large: 59-63cm
• Extra large: 61-65cm

How Should a Road Helmet Fit?

To make sure your road helmet is a good fit, make sure of the following:

• Your helmet covers most of your forehead
• Use the adjustable straps to achieve a snug fit
• Make sure the straps are evenly tensioned
• The straps should be in a comfortable V shape, hanging below your ears
• Make sure you can only fit a single finger between your strap and chin
• Shake your head and ensure the helmet doesn’t move more than an inch

What is the Safest Road Bike Helmet?

The safest road bike helmets will ensure all-around uninhibited vision and protection. Keep a look out for certified helmets or a specific standard that you can refer to. You’ll find a European CE EN1078 standard sticker in the UK that tells you the helmet complies with international standards.

As mentioned above, road cycling helmets prioritise a lightweight and aerodynamic design to help you with longer distances. As road cycling covers a vast range of disciples, including cross-country, you’ll also find a fair amount of versatility in the making, including a variety in:

• The number of vents
• Type of material to achieve lightweight
• Depth of padding

You may also consider helmets featuring MIPS (Multi-Directional Impact Protection System). MIPS is an innovative technological feature that is fitted in higher-end helmets and refers to the additional layer of protection placed inside the shell to help spread and redirect rotational forces, minimising the impact on your head by roughly 10%.

Ultimately, however, you don’t need to opt for a specific brand or price point to get the safest road bike helmet on the market. Make sure to follow the above instructions, and you’ll ensure a great fit and benefit from maximum protection with what you have.

Replacing Helmets

Generally, swapping out your bike helmet every five years will ensure you’re on top of the latest safety standards and not using a worn-out, unusable helmet that isn’t protecting your head to the level you need. Whether it’s the absorption of too much sweat, damage taken from UV light and any corrosive elements that have been in contact with your helmet due to rough weather conditions - these can all impact the rate of degradation of your helmet over a long period.

Karmor kids helmet royal bluearmor

No matter which type you need, all our Decathlon helmets comply with the exact safety requirements to guarantee the required level of protection.

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