What modern road cycling helmets really do beyond protecting your head: Lessons from the Halfords range

A modern cycle helmet is designed to protect the rider in the event of a crash, but will offer a range of features beyond this to ensure that you’re comfortable, however long your ride. Here are the features to look for when choosing a cycle helmet.

TL:DR Helmet fit is fundamental to safety and comfort and there are a range of adjustments built into cycle helmets, but getting the right size is a vital first step. Beyond that, look for good ventilation and low weight. A helmet designed for aerodynamic performance is a bonus, as is a rotational impact protection system such as MIPS.

Fit systems

To be effective, a helmet must fit correctly, so road cycling helmets include features for easy adjustment to different head sizes.

“Correct fit is the absolute, non-negotiable priority with any helmet. A poorly fitting helmet cannot provide full protection and may fail in the event of an accident,” Halfords says.

Head size is measured as the circumference around the top of the head, from the forehead to the occipital lobe – the bump on the back of the skull. Many helmets are available in a range of sizes and include a rear adjuster, usually dial operated, as in the Halfords helmet range, which tightens the rear retainer around the back of the head.

The helmet’s rear cradle can usually be adjusted vertically, so that it sits comfortably below the occipital lobe, again helping to ensure a secure fit.

Different helmets have different internal shapes, so there’s no substitute for trying before you buy to make sure that the helmet suits your head shape; it should be close-fitting and not rock side to side as you ride.

In addition, the length of the straps can be adjusted so that they sit close under your chin. The strap dividers can usually be adjusted up and down to fit comfortably below your ears. You don’t want your straps to flap. A Fidlock buckle, as found in the Halfords Advanced road helmet makes securing and releasing the buckle easier.

“The biggest mistake is choosing a helmet that doesn’t fit well. A poor fit means the helmet might not protect you when it matters most. It’s also important to ensure that the straps and closure system are adjusted correctly (not too loose) and any retention systems are tight,” Halfords says.

For cooler weather, it can be handy to add a cycling cap below your helmet, so make sure that one will fit comfortably.

Weight reduction

Cycle helmets are made of expanded polystyrene foam (EPS), with a polycarbonate shell on the outside to protect it from damage.

EPS is a lightweight material, but cycling helmets typically include channels in the foam layer, which help to reduce weight further, without compromising the helmet’s safety. Almost all cycle helmets weigh under 400g, even in the largest size, and you’re unlikely to feel the weight when riding.

Ventilation

Ventilation and good airflow through the helmet are crucial for rider comfort, particularly in hot weather.

Helmet designers will expend much effort to ensure that airflow through the helmet and over the rider’s head is optimised. It’s usually achieved by deep channels that run front to back through the interior of the helmet, while the Venturi effect is used to speed up airflow and hence help keep the rider’s head more comfortable.

Comfort during endurance rides

The combination of fit, airflow and low weight will result in a helmet that’s comfortable for even the longest rides. On-the-fly adjustability will allow you to fine-tune the fit as you ride.

There’s no substitute for visiting Halfords to speak to its staff and trying on a few helmets to find one that’s comfortable, fits well and matches your budget.

“Most manufacturers recommend changing a helmet every 3 years or after a significant knock. Signs that indicate it's time for a new helmet include any dents or dings, as well as wear on straps,” says Halfords.

Aerodynamics

Modern cycle helmets such as the Halfords Advanced Road Helmet are usually designed to ensure that they offer as little wind resistance as possible. While some helmets are designed specifically for aerodynamic performance, this is often at the expense of airflow through the helmet, as the number of vents may be reduced to lower drag.

Straps will also generate drag, so Halfords reduces the strap width in its Advanced Road Helmet to help reduce their effect on wind resistance.

An all-rounder helmet, such as the Halfords helmet range, will balance aerodynamics with superior ventilation and is a better choice for amateurs not looking for the fastest helmet for racing.

MIPS and rotational impact technologies

Many cycle helmets include additional rotational impact mitigation technologies, which are designed to reduce the transfer of momentum to the rider’s head and are claimed to reduce the risk of brain injury in a crash.

All helmets must be tested to prove that they meet legally mandated crash safety standards before they can be sold, but the inclusion of rotational impact tech may allow a helmet to exceed the mandated test standards.

The best-known rotational impact tech is MIPS, which adds a sliding layer between the helmet shell and the wearer’s head, but there are alternative systems. The Virginia Tech University helmet lab has established itself as the foremost independent test facility for helmets for cycling and other sports and you’ll often see its ratings quoted as stars out of five.

Helmets with MIPS or other rotational impact technology consistently score highly in Virginia Tech’s tests, but it does add to the cost of a cycle helmet.

According to Halfords: “Before choosing a helmet, understand key safety technologies like MIPS or Kineticore. These features are designed to reduce rotational forces in a crash and can make a real difference in your protection.”