How to Choose A Bicycle Helmet

By : Mr Mamil
Updated :

The purpose of this article is to explain and guide you through the process of choosing your bike helmet. We take a look at all the important aspects a good helmet should have and how it should fit your head.

Here are seven things to keep in mind when choosing your bike helmet.

Types of helmet

Each helmet type is designed for a specific cycling discipline. There are subtle design differences between each type which influences their utility and performance. However, there’s nothing stopping you from using one helmet for all types of cycling.

  • Road bike helmets are meant as all-rounder helmets. They’re designed with comfort and ventilation in mind. The majority of road cyclists will be wearing this type.  
  • Aero helmets are very similar to road bike helmets, but with lesser vents (hence less ventilation). Some cyclists prefer aero helmets to have a slight aerodynamic gain on the flats.
  • Time trial or TT helmets are the most aerodynamic helmets. They’ve no air vents and are used either in time trial or triathlon races where the course is flat.
  • Commuter helmets are also referred to as urban or city helmets where they’re stylish and blend with casual clothing.
  • Mountain biking helmets have a front visor to keep the branches away from the eyes. They’re beefier on the back and sides and are heavier.

Fit and comfort

The most important thing about choosing a helmet is the fit and comfort. In my opinion, this is a non-negotiable. Some cyclists give more importance to design and style, but if it doesn’t fit comfortably, there’s no point in having the best-looking helmet around.

Try out the helmet at the shop before buying. Don’t limit yourself to a particular brand and model. Try as many as possible to get a feel of what a comfortable fit feels like.

You can also borrow from your friend to try out the fit if they own one that interests you.

Here are some guidelines on how a helmet should fit.

  • The helmet shell is stable and is comfortably touching the head from front to back. There shouldn’t be any pressure points around the head.
  • The front rim is about one to two fingers in width above your eyebrows when the helmet is placed level.
  • The front rim is not impeding your vision.
  • The side Y straps don’t get in the way of your ears.
  • The adjustable chin straps don’t get in the way when you open your mouth.
  • The retention dial should have enough room for tightening.

Helmet sizing

Helmets come in three sizes; Small, Medium, and Large. Some models have X-Large size, but that’s very rare. Each brand has slightly different sizing and you might not fit the same size across different brands.

If you fall in between sizes, it’s recommended that you size down. Alternatively, if you wear a cycling cap beneath the helmet, you might want to consider sizing up instead.

The table below shows the helmet sizing for some of the leading bike helmet brands.

BrandSmallMediumLarge
Kask50 – 56cm52 – 58cm59 – 62cm
Giro51 – 55cm55 – 59cm59 – 63cm
POC50 – 56cm54 – 59cm56 – 61cn
Lazer52 – 56cm55 – 59cm58 – 61cm
MET52 – 56cm56 – 58cm58 – 61cm

Helmet safety standards 

Bike helmets today undergo a lot of testing before they’re made available publicly. It’s very important to choose a helmet with a valid certification as it ensures that the manufacturers have met the minimum safety requirements.

Depending on your location, the bike helmet you buy can come with either of these certifications.

  • CPSC/ CPSC 1203 (Consumer Product Safety Commission) is a United States standard. All helmets imported and manufactured in the United States after 1999 will have to comply with the mandatory federal safety standards.
  • EN-1078/ CE EN 1078 is a European standard created in 1997. All helmets sold in Europe must meet (or exceed) these standards.
  • AS/NZS 2063:2008 is an Australia and New Zealand standard that has a stricter testing requirement compared to CPSC and CE. Because of this, a similar helmet model with AS/NZS sticker is generally heavier than its CPCS/CE version.

Helmet safety technologies

Safety has improved tremendously in the past decade, especially with the introduction of various breakthrough technologies. Most bike helmets today come with either one of these technologies.

  • MIPS, or Multi-directional Impact Protection System is the most common safety technology used in bike helmets today. It was developed by the Royal Institute of Technology in Sweden. The yellow MIPS liners inside the helmet will slip against each other during impact to help reduce the rotational forces which contribute to concussion and worse, brain injury. MIPS
  • SPIN, or Shearing Pads INside won the German Design and Innovation Award in 2018. Silicone bladders are inserted into the helmet pads which absorb and dissipate the rotational forces upon impact. SPIN can be found only in POC helmets with blue padding.
  • WaveCel was developed by Bontrager and launched in 2019. It’s based on the concept that the WaveCel cellular material will either flex, crumple or glide to absorb the forces upon impact. WaveCel is exclusive to Bontrager helmets and can be easily recognized with the lime green interior.

Even though bicycle helmets today come with advanced safety features, it’s important to replace them in the event of a crash. The helmet will take most of the brunt and sometimes the damage isn’t visible.

Breathability and ventilation

Ventilation is one of the overlooked aspects when it comes to choosing a helmet. Most helmets today have between 10 to 30 air vents depending on the design. All-rounder helmets have more vents while aero helmets have fewer.

If you ride in cooler temperatures, then you can get away with fewer air vents. But when it comes to hot and humid conditions, the more air vents, the better.

Besides the number of vents, pay attention to the vent size too.

Price range

Road bike helmets can cost anywhere from $50 up to $200 today. There are various factors that affect the pricing such as brand, weight, safety technologies, and even colors.

Here are some of my general observations when it comes to pricing.

  • The lighter the helmet, the more it’ll cost.
  • Helmets with MIPS can cost around 10 to 20% more than non-MIPS versions (if available).
  • White helmets are higher in demand and can cost more than other colors such as yellow or green.