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Buying a bike helmet: what you need to know 2019

If you remember the very first time you rode a bike then you probably remember your parents insistence that you wear a helmet—no matter how much it bobbled around on top of your head or cut into your chin. As adults, many cyclists understand and embrace the clear benefits of wearing a helmet.

When it comes to purchasing a bike helmet, there are important factors to consider dependent on your personal requirements and the requirements of a cyclist’s chosen discipline.

Why are bike helmets important?

Every year thousands of cyclists are injured on Britain’s roads. These injuries (and unfortunately some fatalities) occur for a number of reasons and exterior factors that can often by beyond the control of the cyclist.

Whether cycling for leisure or as part of a commute or competitively, helmets can be a vital part of your carefully selected clothing to help you combat the risks that come with riding. It’s hard to control the world around you and completely remove all the risks but you can take control of your personal safety and make the choice to don the helmet and get on with it. Helmet hair might even be a good look for you.

Section 59 of the Highway Code explains the clothing that cyclists should wear in order to keep them more protected in the case of a collision. It states that you should wear a cycle helmet which conforms to current regulations, is the correct size and securely fastened. Currently, despite being advised by Transport for London and the Highway Code, there is no law in the UK that requires a helmet to be worn despite evidence that they can reduce injury.

What about Triathlon law? Well, if you’re competing in a Triathlon and not just cycling on the road then the legislations are notably different. This isn’t just in Britain either; the same rule exists in countries all over the world that understand the importance of a helmet in a competitive medium.

But when do you have to wear the helmet in a Triathlon? Easy answer, it’s not for the swim. To put it simply, your helmet must be on your head and secured before you remove your bike from racking and remain that way until you return from the bike course and the bike is securely racked again. 

The most incidents in Triathlons occur at the bike mount / dismount line and are usually a result of competitors tripping or colliding with barriers and other competitors, so it is important that your helmet is securely fastened at this point. Accidents have also occurred in the transition area where competitors have tripped or slipped as they go out or return with their bike.

Helmets are designed to keep their user safe and with such stakes often on the line and pressure on the shoulders of rider’s, a small mistake doesn’t need to turn into a serious one.

How do bike helmets work?

The main purpose of a cycle helmet is to prevent or reduce the extent of injury to a cyclist’s head during a collision. Cycle helmets must adhere to standard EN1078, which states that a helmet must be designed to withstand an impact similar to an average rider travelling at 12mph falling onto a stationary kerb-shaped object from a height of one metre.

To determine whether the helmet meets these standards, the helmet will go through a number of tests, looking at helmet construction, field of vision, shock absorption and the retention system. Helmets that have met these standards will contain markings so look for a CE marked EN1078 sticker.

Bicycle helmets are manufactured from expanded foam polystyrene. Polystyrene is structurally rigid but it is easy to damage by crushing because it is full of tiny air pockets. As the process of crushing absorbs energy, this makes expanded foam polystyrene the ideal material for bicycle helmets . If the material in the helmet was elastic, the collision energy that was absorbed during the hit would return to the cyclist’s head later on.

Modern cycle helmets also have a micro-shell. The shell is usually between 0.3 and 0.8mm thick and is bonded to the lining material during the manufacture. The micro-shell can help to maintain helmet integrity in an impact, which is important if a second knock to the head occurs in the same accident. The shell is also designed to glide along the road in a collision, instead of bringing the head to a jarring halt, which could cause further injury.

Cannondale’s Quick Cycling Helmet provides comfort and safety with its bonded EPS shell forone-piece integrated design. Not to mention it has a System Integrated micro dial with Ergo-fit EVA occipital pad which offers a precise fit—one of the essential requirements of competition and ensuring safety.

It is also customary for cycling helmets to be fitted with a series of ventilations holes. The more vents that are on the helmet, the cooler the helmet keep the rider. The design also makes the helmet lighter. Not only does the weight of the helmet mean that cyclists will be able to climb and accelerate faster but it also increases head movement, allowing cyclists to be more aware their surroundings and potential hazards.

The MET Fundango and MET Rivale (only weigh 230g) helmets are key displays of this intuitive design and make sure their wearer will be comfortable, safe and ready for challenges.

Types of cycling helmets

Cycling helmets are available in a variety of styles and designs, dependent on the requirements and personal taste of the rider. All helmets should provide suitable safety for the rider and be effective enough to provide the most safety in the environment they will be used.

Kids helmets

A standard has also been designed for younger children’s helmets, known as EN1080. The difference between this and the EN1078 standard is that the chin strap is attached differently to an EN1080 standard helmet. With these helmets, the chin strap is designed to snap off during a collision to prevent the child from choking or being strangled if the helmet snags.

Providing a child with a helmet will help not only their confidence but also give you an improved peace of mind should they suffer a fall or a light collision. Or if they’re not quite a budding rider of their own distinction, they should still be fitted with a helmet if riding with an adult.

The MET Genio helmet has been specifically created with the required safety compliances in mind. Special care was taken to create a child’s helmet that has no internal contact points with the fontanel, the softest part of a developing head. MET Elfo and Genio helmets are also shaped to let kids sit up straight while strapped into a bike seat.

The built-in anti-insect net on the MET Elfo and Genio makes sure bugs and other small bits and pieces are kept outside the helmet. Not to mention they come in a huge range of cool and eye-catching designs!

Road bike helmets

Road helmets can play a big part in every day cycling events as well as competitive ones. Whether you’re going to and from work, cycling around Europe for your next big Birthday or cycling competitively on the road, an appropriate helmet is important.

A perfect example, the MET Crossover helmet is a comfortable and lightweight helmet that is a great all-rounder for fitness riding, commuting or longer weekend adventures. Its smart design provides plenty of ventilation to keep the head cool but it built with a firm exterior shell to lower impact should a collision occur. Not to mention it comes in various colours and has LED safety lighting built in.

Wearing a helmet during your commute can be important no matter how many times you’ve done it. Familiarity and repetition can lead to complacency and a lowered sense of awareness, meaning awareness and focus can be lowered and accidents are more likely to occur as a result.

Mountain bike helmets

Mountain biking can be hardcore and at one point or another it’s inevitable that you’re going to hit the deck. With a rough and sometimes unpredictable terrain, staying safe can help to compensate for other risks riders might not even be aware of—including one another.

That’s why exploring mountains and riding singletrack requires extra impact protection. The MET Roam has an increased coverage around the temple and occipital areas, without adding extra weight. The injection-moulded plastic visor may be flexible, but it won’t act like a spring in event of a crash, or shake around during a ride.

Offering three different positions and two side clips, the MET Roam is compatible with any goggles or glasses on the market. The inner padding has an extended surface area thanks to links between the soft pads, providing stability without disturbing internal airflow.

The MET Roam MIPS helmet is a great investment as it incorporates a multi-directional impact protection system—or MIPS. It adds an extra layer of protection within the helmet shell. It can help redirect dangerous rotational forces that the brain suffer from during a fall or collision. Although these helmets usually look the same as normal helmets, they contain a thin yellow liner. In the event of a collision, this liner slips back fractionally and redirects any twisting forces.

Triathlon bike helmets

Triathlon events require a helmet so if you’re serious about competing, you’re going to have to invest. Yet, any Triathlon rider knows that there’s no use having kit that keeps you back from unleashing your full potential.

The MET Manta helmet was developed with aerodynamic performance in mind. It’s one of the most competitive sprinters’ helmets in the cycling game and can save riders 10 watts at 50km/h. It is created with a crown duct and optimally positioned vents throughout to keep heads cool and lower drag. Not to mention the Manta is only 200g! Keep your head high and unhindered as you fly through personal bests.

With similar qualities, but a more striking design, the MET Drone helmet provides similar energy savings and leads the pack with its sleek aerodynamic form. Its visor makes it a powerful asset for improved sight, especially with anti-fog coating that ensures clarity and the comfortable assurance that the powerful, low-profile magnetics clips will keep the visor in place. Favoured in time trials, this helmet is a favoured race ready companion.

How to choose the right helmet

As stated above, the needs of your cycling lifestyle will impact what helmet you require. Chances are that you don’t need an aerodynamic beast of a helmet for your ten minute commute unless the only time trial you’re up against is your morning alarm. Mountain biking helmets are probably also too bulky and far exceed the requirements needed by a Triathlete.

At many triathlon events you will be asked to wear your helmet when you arrive to set up in the transition area. This allows officials to check your helmet is properly fastened as all too often helmet straps are hanging loose. This makes the helmet ineffective anyway as it would fall off in an accident. The check is quite simple - a rider should be able to get two fingers between the strap and your chin and if you can fit three then the helmet is too loose.

Fit is a crucial aspect of making sure you get the most of your helmet. You do also need to have a helmet that doesn’t hinder your view and provides great ventilation but the fit will be the difference between staying safe or the alternative. If you’re going to wear a loose helmet then you might as well not have bothered.

Helmet sizing

As you can tell, it is hugely important that a helmet fits well, which is why the majority of helmets come in a variety of sizes. If a helmet is too small, it will reside too high and fail to protect the lower part of the head. If it is too big, the helmet will not be securely fitted to the cyclist’s head and could shift during a collision, leading to damage in uncovered areas.

To find your appropriate size, wrap a flexible tape measure around the largest portion of your head—about 1 inch above your eyebrows. You could also wrap a string or ribbon around your head, then measure the length of string with a straight-edge ruler.


General sizing parameters.

  • Extra-small: below 20" (51cm)
  • Small: 20"–21.75" (51cm–55cm)
  • Medium: 21.75"–23.25" (55cm–59cm)
  • Large: 23.25"–24.75" (59cm–63cm)
  • Extra-large: above 24.75 (63cm)

Although helmets can be purchased online, it is recommended that you come instore to be correctly fitted for a helmet. Not to mention you’ll be able to view and feel the huge selection of cycling helmets and try them on to see which suits you best.

When to replace your helmet?

If you are involved in a collision or is dropped with enough force to cause structural damage then a helmet should be replaced immediately. It is also recommended that a cycle helmet is replaced when it starts to show signs of aging and wear and tear.

This is because collisions and wear and tear can cause internal weakness in the helmet—not visible to the human eye. As a result, the helmet may not perform as well if you are involved in a collision or fall.

Where to buy bike helmets in the UK

The team at TRI UK are passionate about everything bikes! That’s why we provide a superior service to all of our customers. Cyclists know they can come into one of our stores, try on our helmets and make sure they get the best fit - but we also offer a fantastic Bike Fit process too.

So whether you need to change your style of helmet, purchase a new one or need one to start you off on your cycling journey, TRI UK has the knowledge you need. With a fantastic stock range, you can keep you and your family safe across different disciplines.

Get the right style and fit for you by checking out our wide range or contacting us today on 01935 414142 or emailing