Posted in Cycle

The proverbial ‘lid’ is now an accepted and even desirable aspect of the cycling uniform. No longer just a protective cycling accessory, it has been radically redeveloped over recent decades, using next-generation materials, frontier-pushing aerodynamics, and top-tier technologies.

Far from the once clunky necessity of old, modern helmets are slick, technically sophisticated, and stylish. In this guide to cycling helmets, we look at the latest styles, features and materials, and how they've been used to create ground-breaking protection for the modern rider. 

How to choose the right cycling helmet for you

The variety of styles, sizes, purposes, and features can be bewildering for those seeking to buy a bicycle helmet, so we’ve set out a complete guide to help you make an informed choice.

Firstly, you’ll need to find your size, which can be done using the charts below. We’ve also explained the various features and safety elements of modern cycling helmets. Finally, we’ve outlined which helmets are best suited to the style of cycling you’re doing.

After that, all you need to do is work out your budget and buy accordingly.

How to find what helmet size you need

Finding the right size of helmet for you is easy and can be done alone in under a minute. Simply use a measuring tape, starting around 2.5cm (about an inch) above your eyebrows on your forehead. Now measure the complete circumference of your head, keeping the tape measure level and above your ears – use a mirror to check it’s straight.

This is the widest part of the head and the measurement on which helmet sizes are based. Ensure the tape measure is a close fit and redo the measurement a few times to ensure the result is accurate. Finding a perfectly fitting helmet is important for the helmet’s effectiveness during an impact and for general comfort. 

Once you have your measurement, use the tables below to establish the size you need to order. These measurements are a rough guide, so be sure to consult the size guide before you buy on the Wiggle product page. 

Metric X Small Small Medium Large Extra Large
Head Circumference 47 - 51cm 51 - 55cm 55 - 59cm 59 - 63cm 61 - 65cm
Imperial X Small Small Medium Large Extra Large
Head Circumference 18 1/2" - 20 1/8" 20 1/8" - 21 2/3" 21 2/3" - 23 1/4" 23 1/4" - 24 4/5" 24" - 25 3/5"

Anatomy of the bike helmet

There are many elements to the modern bike lid, with quality helmets tailoring their components, shapes and features specifically for each discipline.

Key features to consider include:

  • Ventilation – the design, number, and volume of vents
  • Retention system – style of strapping on the rear of the helmet to keep it in place
  • Chinstrap – keeps the helmet on and in a fixed position. 
  • Padding – the amount of padded material in the inner lining of the helmet. Removable padding allows you to wash in inner material, which can be important for hygiene purposes
  • Weight – especially important for competition helmets
  • Reflectivity – to help riders, especially commuters, be seen at night
  • Impact protection – several technical solutions exist, including SPIN and MIPS. These are explained in more detail below
  • Visor – Some helmets, particularly those for MTB, come with removable peaks or visors. A visor on a bike helmet serves two purposes, shielding the eyes from the sun and stopping rain accumulating on goggles or glasses
  • EPS liner - The bulk of the helmet that crumples and deforms to absorb the shock of impact. This can be made of expanded polystyrene or even carbon fibre
  • Carapace - The outer hard shell which protects the EPS liner

How do I know if I need to replace my cycling helmet?

A helmet must be replaced immediately if you are involved in a collision or if it is dropped with enough force to cause structural damage. Keep a lookout for signs of ageing or wear and tear, which can cause internal weaknesses in the helmet that may not be visible.

Some manufacturers, such as Giro and Bell, offer helmet replacement schemes. Meanwhile, Wiggle is the official replacement dealer for KASK helmets. Visit our KASK Warranty page for more information

Ageing or damage will mean the helmet may not perform well in an impact situation.

How your cycling helmet should fit

Your helmet should allow for good all-around vision as well as protection.

The upper straps should form a ‘V’ shape just beneath the ear, and with the helmet on, you should not be able to fit more than two fingers between the chin strap and your chin. The buckle and chin area of the strap should fit close to the underside of the chin once fastened, but allow you to open your mouth to eat an energy bar or drink water from your bottle.

There should also be a maximum gap of around two finger widths between the front of the helmet and your eyebrow line. 

Helmet safety features

As mentioned earlier, advanced research in the industry has led to the creation of new helmet safety features. Below is some additional information on the latest advancements, which you may want to consider before choosing your helmet.


MIPS stands for Multi-directional Impact Protection System. It is described as ‘slip-plane’ technology and works by reducing rotational forces that can result from certain impacts.

See our full description on the MIPS system

Shop MIPS Helmets at Wiggle

MIPS Spherical

For their new Aether MIPS, Giro has developed a new standard of advanced protection. MIPS Spherical embeds the MIPS liner between layers of EPS foam so it doesn't sit directly against your head. This means comfort and cooling power is not compromised. 

Introduced by helmet specialist POC, SPIN was developed to counter the effects of oblique impacts. The system uses pads on the inside of the helmet that help the head continue to rotate during impact, lessening the forces on the brain.

Helmet safety standards

Depending on your country, cycling on the road or competing in a race may legally require the wearing of a helmet certified to a specific standard or an international equivalent. All helmets sold on Wiggle are certified, labelled with a European CE EN1078 standard sticker, and comply with a range of international standards. If you live in the US, your helmet should conform to the US Snell B90/B95 standard, while Australians should ensure their helmet meets the AS/NZS 2063:2008 certification.

What type of helmet do you need?

Bicycle helmets are specifically designed to suit your riding style and discipline, whether that’s casual commuting, aggressive downhill riding, or searing aero speed cycling.

We’ve looked at some of the most popular cycling disciplines and the type of helmet best suited for their unique demands.

This should help you to choose the best lid for your purposes. And if you’re buying for a child, we have advice that should help you too.

How to find the best road riding helmet

Road cycling helmets are designed to be lightweight and offer an aerodynamic advantage for riding long distances. They are often built with versatility in mind and can be used in a variety of disciplines, such as cross-country riding. Road bikes also feature numerous vents to allow heat to escape during exhaustive rides or uphill climbs. Elite level helmets use ultra-light materials and offer great ventilation and protection.

Kask Protone Road Helmet

Developed in collaboration with UCI world tour pros, the Protone strikes a perfect balance between aerodynamic performance and cool comfort. 

  • Made with in-moulding technology for extra durability without extra weight
  • Removable padding treated with antibacterial and antimicrobial finishes for freshness
  • Weighs only 230g 




MET Trenta Road Helmet (MIPS)

Optimised for outstanding performance in the peloton. The tube-shaped tail offers up to a 7% reduction in drag compared to traditional road helmet designs.

  • Equipped with MIPS-C2® which limits the rotational impact in the event of an accident
  • Hand-washable air mesh comfort pads
  • Safe-T Orbital Fit System for maximum comfort




HJC Valeco Helmet

HJC Valeco Helmet

The Valeco offers features you would expect at a pro-level but at an affordable price, making it one of the most popular models in the HJC range.

  •  Fine-tuned in HJC's very own wind tunnels for optimum aero performance.

  • 12-port ventilation system channels cooling air over the head.

  • Fully adjustable occipital cradle for a secure and comfortable fit.

Shop road helmets at Wiggle

How to choose the best aero helmet

Aero helmets bridge the gap between everyday road helmets and the elite time trial helmets. Designed to reduce drag while providing ease of movement, these lightweight and compact helmets are perfect for triathlon entrants, or competitive road cyclists.

Giro Aether Helmet (MIPS)

A game-changing lid that elegantly combines high-tech MIPS Spherical protection with pro-level performance.

  • 11 Wind Tunnel vents channel air internally over the scalp to keep you cool.
  • Multi-density EPS foam plus MIPS Spherical provide protection from a range of impacts.
  • Roc-Loc® 5 fit system for a completely customisable fit.





Kask Valegro Road Helmet

Designed for optimum aerodynamic advantage and super-cool comfort, the Kask Valegro is the helmet of choice for Team Ineos. Delivering high performance for road cyclists who want to get the most out of every ride.

  • 36 vents designed for supreme cooling without adding drag.
  • Patented MIT Technology adds a polycarbonate shell on top for complete protection.
  • Octo Fit design uses gel pads and floating cradle contact points for a perfect fit.

Shop Aero Road Helmets at Wiggle



Choosing the best time trial helmet

Time trial helmets are at the cutting edge of aerodynamic engineering. Designed for slicing seconds off a crucial race time, their core purpose is to give you a winning edge along with protection against a high-speed impact.

kask utopia road helmetKask Utopia Road Helmet

A heavenly ride awaits you with the Kask Utopia Road Helmet, delivering ideal collision protection and perfectly positioned vents for that added advantage of improved aerodynamics. 

  • Made with INMOLD technology
  • Anti-bacterial padding – washable and removable
  • Strategically position vents





giro vanquish mips aero helmetGiro Vanquish MIPS Aero Helmet

One of the most technologically advanced road cycling helmets on the market, the Giro Vanquish MIPS Aero is filled with features to streamline airflow for reduced drag and increased aero. 

  • Integrated MIPS technology
  • Magnetic Vivid shield
  • Wind tunnel ventilation





kask mistral aero helmetKask Mistral Aero Helmet

Kask's pro-favourite Mistral Aero Helmet has been ridden to multiple successes by Team Sky. The helmet has been specially engineered to offer high performance for both track and triathlon use.

  • 8 slots in helmet for strong air flow to keep the head cool
  • Chin pad with eco-leather chinstrap
  • Magnetic Visor Attachment

Shop Time Trial Helmets at Wiggle



Helmets for the trail:

How to pick the best open-face mountain bike helmet

mountain biker riding bike through the forest

Mountain bike helmets offer protection in place of aerodynamic considerations, giving you extra coverage, and durability to meet the needs of the trail.


Fox Racing Speedframe Pro MTB HelmetFox Racing Speedframe Pro MTB Helmet

A go-anywhere, do-it-all, fully-featured trail-slaying helmet that offers fabulous levels of protection and all-day comfort.

  • Improved protection with dual-density Varizorb EPS
  • Fidlock® SNAP helmet buckle
  • 360Fit system allows you to dial in your perfect fit every ride






100% Altec MTB Helmet100% Altec MTB Helmet

100%'s Altec MTB helmet ensures you'll enjoy confidence-inspiring protection and unrivalled comfort when out on the trails, no matter how hard you push your limits.

  • 14 Point Smartshock® Rotational Protective System
  • Massive airflow with 15 ventilation ports
  • Multi-point adjustable visor designed for maximum vision

Shop MTB Helmets at Wiggle




Full-face MTB helmets

Full-face MTB helmets are favoured by Enduro and downhill riders for their important face-protection qualities.

Fox Racing Rampage Pro Carbon Matte Helmet

Fox Racing is revolutionising confidence on the trails again. Introducing a new Fluid Inside system that provides better protection against both linear and rotational impacts.

  • Made with all-new dual-rotational management system: MVRS + FLUID
  • Removable & washable Dri-Lex comfort liner
  • Multi-Composite Technology (MCT) shell construction




SixSixOne Reset Helmet

Optimised for outstanding performance in the peloton. The tube-shaped tail offers up to a 7% reduction in drag compared to traditional road helmet designs.

  • Lightweight ABS shell
  • Large angular vents increase cold air intake and heat exhaust flow through
  • Sculpted eye port for great vision and goggle fitment 

Shop full face MTB Helmets at Wiggle




Picking the best XC helmet

While the less technical cross-country trails pose less of a risk of a high-speed fall, the greater demand on your stamina means you need much better ventilation to stay cool throughout an event.

Fox Racing Dropframe Pro MTB Helmet

Fox Racing's most capable open-face mountain bike trail-riding helmet provides incredible protection with outstanding airflow and comfort.

  • Fidlock® SNAP helmet buckle provides quick and secure entry and exit while wearing gloves
  • Improved protection with the dual-density Varizorb EPS
  • Securely fixed visor is positioned to channel airflow comfortably for the rider




MET Parachute MCR Helmet (MIPs)

Striving to produce innovative, inspiring and safe products for the riders of today, MET has created the ultimate convertible helmet.

  • MIPS brain protection system
  • Flexible, adjustable injected visor
  • 21 vents with internal air channelling

Shop XC Helmets at Wiggle





How to pick the best BMX helmet for you

BMX helmets also feature full face and open face. Full face helmets are more likely to be worn during BMX racing, while open face (skate style) helmets are more common on flatland riding and dirt jumping.

Fox Racing Flight Sport Hardshell Helmet

If you're obsessed with protection and comfort, this stylish hardshell helmet welcomes only the finest levels of performance for a truly remarkable session.

  • M9™ segmented EPS design
  • Fox Varisorb™ multi-density impact reduction system
  • Thin ABS shell for reduced weight

Shop BMX Helmets at Wiggle





Choosing the best kids helmet

Wiggle’s range of helmets for kids and youths feature industry-leading safety standards and come in a variety of colour schemes designed to encourage their use.

Bell Sidetrack Kids Helmet

Designed for 5 year olds and up, the ready-for-action style, complete with visor, gets young riders motivated to ride.

  • ErgoDial™ Fit System
  • In-Mold Polycarbonate Shell
  • Pinchguard™ Buckle






MET Genio Kids Helmet

MET have drawn on their experience and expertise in creating the best possible helmets for children to create the Genio. They've focused on features specific to the needs of young riders.

  • Anti-allergenic interior padding is hand washable and an insect net is built-in
  • Anti-pinch buckle and anti-slip cam divider
  • Integrated visor for added protection

About the author

Damien Whinnery's picture
Damien Whinnery
Published on: 08 Jun 2020

Fascinated by fitness, serious about sport, and joyous about the gym