How To Measure For A Motorcycle Helmet – A Size Guide

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While it is easy to get carried away by the exhilarating nature of motorcycling, it is crucial to take appropriate precautions to protect yourself from accidents and injuries. A helmet is the single most important piece of safety gear that can save you from potentially fatal damages in case of an accident. 

However, for a helmet to work, you need to get one that fits you correctly. Therefore, buying a helmet requires a little research to understand the different types and shapes to choose the most suitable one. This guide will walk you through all the key aspects you need to keep in mind before purchasing this critical motorcycling safety gear.

Helmet Fitting Is Crucial

Your helmet fitting will determine how much protection your helmet will actually provide in the event of an accident. In fact, a DOT (Department of Transportation) Safety rating will only be valid if your helmet is correctly sized. Helmets come with an impact-absorbing liner designed to cushion your head and manage forces during an impact. Some also feature built-in slip-liners designed to reduce injuries that could be caused by rotational forces. 

If these liners don’t fit well against your head, your safety is compromised because they don’t function as intended. On the other hand, helmets that are too tight can be uncomfortable and even painful. This can be so distracting and unbearable, that you eventually stop wearing one. 

The best helmet is the one that fits snugly and allows you to ride without inhibiting your range of motion or ability to safely operate your motorcycle, while also being sturdy enough to bear the brunt of impacts.  

The Types of Motorcycle Helmets

Like motorcycles themselves, motorcycle helmets significantly vary in price and style. There is a myriad of options available in the market these days. While having so many options is fantastic, it can also be overwhelming. So, let’s go through the types of helmets to help you choose the one that’s best for you.

1. Open Face Helmets

These are the least restrictive and also the least protective type of helmets. The helmet shell does not cover the face or chin of the rider, hence the name. They can be “half” helmets or “three-quarter” helmets depending on the area of the skull they cover. These tend to be inexpensive, but they also lack features provided by most helmets these days.

2. Full Face Helmets

As the name suggests, these helmets fully enclose the rider’s head. They provide maximum protection from impacts and other environmental elements. However, these helmets offer the least ventilation.

3. Modular Helmets

Modular helmets are a subset of full-face helmets. These helmets have a hinged mechanism that allows you to convert your full-face helmet into an open face helmet by retracting the face shield and chin bar. Modular helmets are great because they allow you to choose between a ventilated open face helmet or a sturdy full face one depending on your needs. 

4. ADV Helmets  

ADV or adventure helmets incorporate elements required for both on and off-road riding. If you find yourself frequently transitioning from the streets to dirt trails, these helmets are great.

5. Dirt Helmets 

Dirt helmets are made exclusively for off-road riding. These helmets also do not require a DOT Safety Rating and might not be street legal in many areas. 

Determining the Shape of the Helmet

Before learning how to measure for a motorcycle helmet, we need to look at the helmet shape. The shape of the rider’s head plays a crucial role in determining the correct fit. All helmet manufacturers design helmets to suit a specific head shape. There are three primary designations of head shapes-

1. Long Oval Shape

This head shape measures longer front-to-back as compared to the side-to-side measurement. 

2. Intermediate Oval Shape

This is the most common head shape, and most helmets are manufactured for this category. The front-to-back measurement of this head shape is only slightly longer than side-to-side.

3. Round Oval Shape 

This head shape has almost identical front-to-back and side-to-side proportions.

An easy way to determine your head shape is by asking your friend to take a photo of your head from above. Make sure to flatten down your hair as this could obscure the form of your head. Look at the picture to determine the proportions of your head. Once you’ve figured that out, you’re now ready to move on to finding the right helmet size.

Sizing a Motorcycle Helmet 

Figuring out how to measure for a motorcycle helmet is easy. All you need is a seamstress or a tailor’s tape measure. Begin by wrapping the measuring tape around the fullest part of your head. This should be just above the ears or half an inch above your eyebrows for most people. For the most accurate measurement, we recommended asking a friend to help you out.

Once you’ve taken the measurement, compare it to motorcycle helmet size charts, which are easily accessible online. Remember, each manufacturer has sizes specific to their models, and therefore, some variance is common between brands. Therefore, trying out the helmet is crucial before purchasing it.

Trying the Helmet on and Checking for a Proper Fit

So, you’ve figured out your head shape, measured the helmet size, and narrowed down the options. Now, it’s finally time to test your new helmet.

While trying on your helmet, you will need to spread the straps apart to fit it over your head. You may even need to adjust your ears in place to avoid discomfort. Remember, helmets are not designed to be comfortable while you put them on, and a little adjusting is normal. Your focus should be on how your helmet fits after it is locked in place.

How should a helmet feel once you wear it on? It should be slightly tight when initially worn, as most helmet liners break-in at least 15 to 20 percent after the first few hours of riding. In fact, the majority of your helmet’s interiors should be in contact with your head.

Simultaneously, the fit shouldn’t be so restrictive that it causes any pain or severe discomfort. Suppose you notice any “hot spots,” i.e., areas where your helmet’s interior places excess pressure on specific points of your face or head, you should try another fit. 

Finally, vision is crucial while on the road, so make sure your helmet allows you to have a good peripheral vision. Also, the face shield should not obscure your view in any way, and tinted visors should only be used on bright, sunny days.

Final Thoughts

A well-fitted helmet contributes to a safe and comfortable journey, while an ill-fitted helmet causes pain and discomfort, leading to dangerous distractions. Furthermore, a poorly-fitted helmet won’t be effective at protecting you from fatal impacts.

Therefore, finding the right type of motorcycle helmet that fits snugly is crucial for your comfort and safety on the road. Be thorough in your research and make sure you learn how to measure for a motorcycle helmet accurately so that you can enjoy the road for years to come. 


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Nathan Olvera

Nathan Olvera

Nathan was born and raised in Nevada where he spent some of his earliest days cycling around the neighborhood and gradually developed a great deal of love for motorbikes.
Nathan Olvera

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