​More weight, more protection: Why are MTB helmets getting heavier and heavier?

In the past, there was one rule that applied above all else to mountain bike helmets: lighter is better. Today, the trend seems to be reversing. Many of the latest trail, enduro and e-MTB helmets weigh noticeably more than comparable models from ten years ago. But the extra grams aren’t a step backwards; they’re a reflection of a new safety philosophy. We’ll explain why modern MTB helmets are getting heavier, what protection systems lie behind this trend, and what role e-bikes, enduro races and safety standards play.

Why aren’t there any lightweight MTB helmets any more?!

A reader recently wrote to us with a rather desperate-sounding enquiry:

I’m looking for a helmet that isn’t as heavy as lead. The POC Tactic, Kortal and the like weigh nearly 500 grams. The Specialized Ambush 3 is listed as weighing 360. It’s also become really rare to find a helmet that doesn’t start at over 200 euros and is still lightweight, fits well and is of good quality.

Yes, I thought to myself, I can’t agree more. Let’s just take a look at the Specialized Ambush in question, which has been around since 2016 and is now in its third iteration. You can really see how it’s evolved here.

In 2016, we reviewed the first Ambush:

The Ambush is the archetypal enduro helmet. Thanks to its aramid reinforcements and deep-drawn shell, it offers excellent protection whilst remaining very lightweight. The fit and adjustment system are well thought out, as is the visor. The ventilation is top-notch. Other helmets are better built. Nevertheless: a well-deserved test victory.

At the time, the Ambush – which did not yet feature the MIPS system – weighed 279 grams – and it quickly became my absolute favourite helmet, until I had to replace it following a crash. Shortly afterwards, the Ami helmet became available with rotational protection as well, and even with that it still managed to just under 300 grams. Compared to the weight of today’s all-mountain helmets, that was still quite a statement.

But the ambush also became significantly more severe: Version 2, with its curved, organic shape, already weighed in at around 360 grams in size M. At that time, MIPS was already more or less standard on high-quality MTB helmets.

The Specialized Ambush 3 on the market, and what can I say: the weight spiral just keeps going round and round. A whopping 442 grams weighs as much as the former flyweight – in size L, admittedly. You can find the full review via this link.

Does more weight mean better protection?

And, one might rightly ask, is the Ambush 3 at least safer than the lightweight original model? Fortunately, the answer is YES. If you look at the data from the internationally recognised test laboratory Virginia Tech, a clear trend emerges:

• The Specialized Ambush 1, which had achieved very good results in our 2016 lab tests, scores only 15.66 in the Bicycle Helmet Rating, placing it at 225th place.
• The rather heavy Ambush with MIPS scored 13.96 points and came in at 190th place.
• With a score of 9.88, the Ambush 2 performs significantly better, 45th place.
• The current Ambush 3 even manages to achieve a score of 9.11, reaching 29th place the league table.

In many cases, therefore, greater weight also means greater safety – although this statement cannot, of course, be generalised, as there are certainly lightweight helmets that also offer very good protection. But why is it, actually, that MTB helmets today are often significantly heavier than their counterparts from the past?

A larger head covering adds to the weight

If you compare a modern trail or enduro helmet with a model from the early 2010s, you’ll spot the difference straight away: today’s helmet shells extend significantly further over the back of the head, the temples and the sides of the head.

This additional protective shell is no coincidence. Accident analyses have shown that, in mountain bike crashes, the back of the head and the sides are particularly at risk. Manufacturers are responding accordingly with larger shells and more shock-absorbing material.

The downside is obvious: more material almost inevitably means more weight. Whilst an ambitious XC helmet used to often weigh less than 250 grams, modern trail and enduro models frequently weigh between 330 and 450.

Safety systems: MIPS, KinetiCore, Turbine 360 & Koroyd

One of the main reasons for the increase in weight lies inside modern helmets. Manufacturers are increasingly investing in technologies designed not only to absorb direct impacts but also to reduce rotational forces.

MIPS: The industry standard

The Swedish MIPS (Multi-directional Impact Protection System) is now regarded as the de facto standard in the cycling sector.

There is a flexible sliding layer between the helmet shell and the head. In the event of an oblique impact, the helmet can move a few millimetres relative to the head. This is designed to reduce rotational forces, which are considered to be one of the main causes of concussions.

Depending on the model, MIPS adds just a few grams to the weight. Overall, however, the system contributes to the higher total weight of modern helmets.

360° Turbine Technology

The South African brand Leatt utilises what is known as 360° Turbine Technology. The helmet contains small, turbine-shaped shock-absorbing elements made from a special polymer material. These are designed to reduce both linear and rotational impact forces.

The advantage is that these components do not require a separate sliding layer, unlike MIPS. However, they also increase the amount of material used and the complexity of the design.

Lazer KinetiCore

With KinetiCore, Lazer takes a different approach. The rotational protection technology is integrated directly into the EPS foam structure.

Instead of additional components, defined crumple zones are created within the helmet. In some cases, this reduces weight compared with traditional MIPS solutions and allows for better ventilation. KinetiCore demonstrates that greater safety does not necessarily mean more weight.

Koroyd

Smith’s distinctive greenish honeycomb material is now featured in many premium models. Koroyd consists of thousands of welded tubes which are designed to collapse in a controlled manner upon impact, thereby absorbing energy.

In some cases, this technology offers a higher level of protection whilst using a comparatively small amount of material. Nevertheless, the additional structure often increases the overall weight compared with a construction made solely of EPS.

New standards – greater safety, greater weight

In addition to safety systems, it is, above all, stricter certification requirements that are driving development forward.

EN 1078 – The classic standard for cycle helmets

The European standard EN 1078 has formed the basis for bicycle helmets for many years. It sets out basic requirements for impact absorption, retention straps and field of vision.

However, for modern trail and enduro riding, many manufacturers have long since found this standard to be insufficient. As a result, many current helmet models have additional certifications:

CPSC – the most important US helmet standard

CPSC stands for the Consumer Product Safety Commission and is the safety standard for cycle helmets required by law in the USA. Since 1999, all cycle helmets sold on the US market must comply with the requirements of CPSC 16 CFR Part 1203.

The CPSC standard tests helmets for higher impact energies or greater drop heights than EN 1078. This means that helmets must be capable of absorbing stronger impacts. Furthermore, the CPSC test includes additional anvil shapes (impact bodies), including a hemispherical test body (hemi-anvil), which is not required under EN 1078.

Furthermore, the CPSC tends to require a greater coverage of the back of the head, which is why helmets are often a bit bulkier.

NTA 8776 – The e-bike standard

The biggest factor affecting weight in recent years is the NTA 8776 standard. Originally developed for S-pedelecs with speeds of up to 45 km/h, this standard requires a higher impact energy absorption capacity and an extended protection zone at the back of the head.

More and more trail and all-mountain helmets now also carry the NTA mark. For manufacturers, this often means thicker EPS foam, larger shells and reinforced constructions. As a result, NTA-certified helmets often weigh between 30 and 100 grams more than comparable models without this certification.

The boom in enduro and bike parks is changing the requirements

Mountain biking has changed fundamentally over the past ten years. Whereas marathon and cross-country races used to dominate, the focus is now on enduro races, flow trails, bike parks and technical descents. Modern mountain bikes allow for higher speeds and more challenging terrain than ever before.

This is also changing the requirements for helmets. Riders today are much more willing to accept a few extra grams if it means they are better protected in the event of an accident. Many manufacturers now deliberately adhere to the ‘safety first’ philosophy. This explains why weight is often no longer the top priority in development.

Comfort and extra features also add to the weight

Last but not least, the range of features offered by modern helmets is constantly expanding. Features that are now standard include:

• large, multi-position visors
• Sunglasses garages
• Action camera mounts
• Fidlock magnetic fastenings
• complex adjustment systems
• Integrated spectacles or goggles solutions
• additional ventilation ducts and reinforcing structures

Each individual feature adds just a few grams. Taken together, however, this results in a noticeable difference in weight compared with older models.

Conclusion: Those extra grams are usually money well spent

Yes, mountain bike helmets do tend to be getting heavier. However, this is not due to a lack of development work, but to significantly stricter safety requirements.

Greater coverage, rotational impact protection systems such as MIPS, KinetiCore, Turbine and Koroyd, stricter standards such as NTA 8776, and the demands of modern enduro and bike park trails mean that today’s helmets have to perform better than ever before.

The good news is that, thanks to modern materials and clever designs, the weight increases at a much slower rate than the level of protection. Or to put it another way: those extra 50 to 100 grams on your head can make all the difference in an emergency.