Bike Helmet Lifespan: When Should You Replace a Dropped Bike Helmet?

bike helmetLots of times I’ve been wondering if I ruined the safety of my helmet by accidentally dropping or hitting it with something. Spending time checking for cracks used to waste a lot of my time. After all, new helmets aren’t that cheap. With that said, wondering if I should replace a helmet all the time wasn’t really a comfortable feeling.

Well, in time I realized that if you crash with it and hit it then, it’s time for a new one. However, it’s not that easy to break a helmet only by dropping it from a few feet, even on a hard surface. Although, five or more feet and you may already have a problem.

Bike helmets look like they are durable and resistant to breaking. I mean, something that’s made to protect your head should be like that. But, are they?

Not that much actually. However, there is a reason helmets aren’t more resistant to breaking.

It all comes down to the material. The foam that’s used for bike helmets is the best lightweight impact-absorbing material. And that is what’s actually important. You don’t need your helmet to be durable if the first time you fall you end up with head trauma. You want it to protect your head perfectly.

In order to give you the best protection possible, a helmet gets damaged instead of your head.

Safe to Use Mountain Bike Helmet Brands

The things I mentioned, unfortunately, don’t apply to any helmet.

There are lots of bicycle helmet manufacturers out there, and some of them don’t do any tests on their helmets. They even break too easy or are simply not sitting on your head properly. Get a poor quality helmet and you may do even more damage to your head because if it’s not properly designed it can twist your neck in a fall.

Make sure that your helmet is bought from a bicycle-specific shop, or at least from one of the major bike safety gear brands. Unless, you want to decently research the helmet market, in which case you may find some amazing helmets from smaller brands that follow all the safety equipment standards.

Bike Helmet Testing Standards

There are certain testing standards that every bike helmet manufacturer should follow. In the US every helmet in order to be legal must pass a test of dropping from 4-7 feet onto a hard surface, usually an anvil. Unfortunately, the foam used may vary and production isn’t always monitored as it should be so you never know.

As I mentioned, I’m un/lucky to drop my helmets lots of time and I can safely say that 5 feet drop is a good rule of thumb on hard surfaces. Any higher than that is likely to create small cracks and the helmet needs to be replaced.

European or Asian manufacturers go through the same process but there are still lots of brands that can’t be trusted. There were cases of avoiding safety tests and some countries don’t even care if there are any safety standards or not. So major brands, especially those coming from the US market are the only safe option outside of the US and EU.

Helmet Dropped On a Concrete vs. Trails

Testing is done on a hard surface, so a concrete road is where you can easily know the limits. However, out there on a trail is a completely different story.

Your helmet may hit the soft dirt or a patch of grass and not be damaged at all. But then again, even on a small drop it can land on a sharp rock and crack when it seems like it shouldn’t.

Especially, if you fall and hit it while wearing it. Your body will have enough momentum to damage a helmet even when you hit dirt or grass. In case you crash with it, a replacement is necessary immediately. If you are in the middle of a ride, finish it carefully and make sure you end the day unless you have a replacement with you.

Invisible Cracks In a Bike Helmet

Some people might tell you that it’s okay to use a helmet in which you crashed again. I wouldn’t recommend that. I would even advise not to ride until you can buy a new one.

Damage isn’t even visible most of the time. Helmets have that central ridge of foam that keeps a helmet together connecting both sides and making it flexible enough to absorb contact. That’s the spot where invisible cracks usually happen, exactly where you need them the least.

In time the helmet will bend in that spot and the crack will get bigger. Once you crash again it won’t absorb the hit, but instead, break instantly and leave your head unprotected.

That’s why replacing a helmet after a crash is a must. It’s simply not worth the risk.

The Spot Where It Took a Hit

A bike helmet doesn’t need to crack to become unsafe for usage. Foam can become dense at a spot where it took a hit. You will most likely be able to see this by pressing on the outside shell.

Bending rarely happens with today’s helmets because they are made to break before they bend. On the other hand, the foam can become dense quite often on taking hits. Especially if the impact was from a smaller blunt object like a root or stone.

That spot won’t absorb any impact later on. The chances of falling and hitting it in the same spot are low but it’s a valid concern nonetheless.

Bicycle Helmet Expiration Date

There are some industry standards for safety equipment that require expiration dates in order to predict failures due to material degradation. In other words, some materials lose their functionality over time. And since we are talking about safety, an expiration date is needed to prevent the industry’s responsibility if the material is so degraded that it causes safety equipment failure.

The expiry periods are usually set years before the equipment actually gets unsafe but it’s sort of a useful guideline to follow.

Lately, I’m seeing dozens of “know it all” people that claim expiration and degradation as bs. To be honest, I’m disgusted by their ill-advised comments.

They are using an argument about helmet foam not really degrading. It is actually degrading but really slow and it gets hardened so it’s not really a major safety issue, especially if we consider that it will never reach a point of losing impact absorbing properties.

But what about other materials?

Other Parts Degrade Over Time

The plastic shell, for example, is the single most important element of good safety. The foam itself is useless if there is nothing holding it together. It would simply break apart on impact and you would hit your head like it was never even there. And that very plastic is known to degrade faster than anything else. It’s affected by the sun and even by the air itself. In time the plastic shell will lose its elasticity and break like glass on impact. A helmet like that is completely useless.

All the straps and the ratchet are connected with plastic parts. The very same plastic that during the years of use starts to easily break when tension is applied.

The padding wears out as well and it’s quite important to keep a helmet in a proper position.

All in all, expiration periods are not to be neglected on any safety equipment. They may seem like money grabbing trick from manufacturers but they are not.

Don’t risk your health for a few bucks.

Properly Wash Your Helmet – Lasts Longer

Sweat and strong washing chemicals can damage a helmet and degrade materials.

It’s important that you wash your helmet after each sweaty ride. Most of the cleaning products and hot water won’t be good for the foam and straps, so try to avoid it. It’s best to use mild soap with warm or cold water.

I would recommend to let it air dry because heat drying can degrade the foam in the same way a hot water can. If you do this properly, you can expect your helmet to last for a very long time. That is of course if you don’t crash often.

Motorex Helmet Care is better than any bicycle helmet cleaner out there. At least that’s what my experience tells me.

Other Reasons to Replace a Mountain Bike Helmet

You Don’t Have a Helmet Specific to Your Type of Riding?

It’s not quite safe to use cross country helmets for trail/enduro riding and especially not for downhill riding. The way you crash is not the same on different types of trails. And the terrain itself can vary between dirt, rocks, roots, and trees which affect the way you crash and your safety when it happens.

Enduro helmets have a thicker structure than XC helmets. Mainly on that central part of foam that keeps the sides together. In addition to that, they have much better protection in the back, reaching down closer to your neck.

However, even though trail riding and enduro racing have lots of downhill sections, helmets made for these are still not good enough for real downhill racing. The speed is much higher because downhill trails are based more on pushing the limits. This type of riding requires a full-face helmet, a good one to be precise. Anything else will get you severely injured.

You Have an Older Helmet Without Plastic Shell

Vintage helmets are cool looking but completely unsafe. Especially, because they weren’t even made specifically for mountain biking and without any safety regulations.

Most of them don’t have a plastic shell which is extremely important, as I mentioned above. It’s what keeps the foam from breaking apart.

Even the ones that had a plastic shell were glued to the foam. A glue, which by now, isn’t even keeping it glued as it should. In any case, I wouldn’t recommend using anything older than 5-8 years anyway.

No CPSC, ASTM, Snell or EN1078 Sticker

There are stickers that state which safety regulations or tests were done to make sure the product is safe to use. Some countries don’t require any regulations on safety equipment so you need to be careful about those helmets.

In the US and most European countries, mainly the EU, there are strict regulations and controlled tests so you don’t need to worry about it. Unless it’s an older helmet. These regulations changed multiple times during the last few decades in order to improve consumer safety.

Here applies the same general rule as for any old helmet. If it’s older than its expiration date, it probably has outdated safety regulations too.

I understand it may seem like it’s not that relevant, safety is not something that’s invented in the last 10 years, but the way mountain biking is becoming more and more technically advanced so the risk and severity of injuries increase as well. Safety regulations for mountain bike helmets were improved several times to follow these changes on the trails.

You Can’t Adjust Your Mountain Bike Helmet Properly

The thing is, in most shops that sell helmets there is no one with enough knowledge to assist you when choosing a helmet. Sizing is a bit tricky with them because it’s not only the size that you need to worry about.

Our heads are very different in shape and it’s often hard to find a good fit. For most trail/enduro helmets that shouldn’t be that big of a deal simply because they will cover everything no matter how good the fit is. As long as you can tighten it and it’s not too small you will be perfectly safe out there on the trail.

Some cross country helmets, on the other hand, won’t fit everyone as they should. Not being able to adjust it properly will result in it falling off during crashes or twisting on your head which may lead to head and neck injuries.

This is a reason as good as any to change your helmet.