If you’re looking to upgrade or replace your motorcycle helmet, how do you know what size to buy? We here at RideApart are big fans of protecting our brains, so let’s look at sizing and fitment when it comes to helmets. If you’ve already bought a helmet, and it’s too tight or too big, can you still wear it? Well, it depends.

First, in order to keep yourself out of this predicament, keep in mind that not every helmet manufacturer is on the same page when it comes to sizing. A size medium helmet from one brand can be a slightly different size than a medium in another, so assuming you’ll be the same size in every helmet is a mistake. Every manufacturer will have a size chart available; measure your head (just like measuring for a hat) and pick the one that’s correct.

Also, if you are right on the edge between sizes, or experience discomfort in a specific spot, you can often swap out the helmet inner lining for a different size to customize your fitment. A good motorcycle gear shop will do this for you at no extra cost. An online retailer will have cheek pads for sale, but they will cost you extra. If you are new to motorcycling, it is worth it to find a good, specialty brick-and-mortar gear shop with salespeople trained in helmet fitment. They will also often price-match online retailers’ prices. If your current helmet is a bit loose in your jaw line, it's worth it to buy a set of slightly thicker cheek pads to take up that extra space.

Helmet shape is also important. If you try on helmets and experience a common pressure point, for instance, the front of your forehead, you may be trying helmets that are too round, and should try an intermediate oval or long oval shape for better comfort. Do not size your helmet up to alleviate a pressure point. Your helmet should fit very snug but pain-free. There should be no gaps between your scalp and the inner liner. If it wobbles around on your head it can shift in the wind, will not protect you in an accident, and may even come off. If this is the way your too-loose helmet fits, you should not wear it. Go find a helmet that actually fits you.

You should also know is that helmet shells come in different sizes, and this is one of the things that can differentiate a bargain helmet from a pricier one. It costs the manufacturer more to make more shell sizes; the correct size helmet shouldn’t make you look like an apple on a stick. When you are shopping for a helmet, pay close attention to the number of shell sizes available. Does the helmet come in extra-small to double extra-large internal sizes but only three shell sizes? That means only the foam and liner correctly proportioned to the shell size will be ideal; the outliers can have a ton of foam or not enough. If you need to add a bunch of foam, or take a lot of foam out of a helmet to make it fit, it doesn’t really fit you, and you should enlist the help of a helmet fitment expert at your friendly local gear shop.

Why is foam important? Too little means your head might not be well-protected in a crash. A too-big shell with a really thick liner can mean too much wind resistance and too much weight on your neck.

A well-fitting helmet will give you a bit of “fish-face.” It should be a small struggle to get the helmet on. Your cheeks should be a bit squished, you should not be able to eat anything or chew gum in there. Turn the helmet side to side and the skin on your scalp should move with the helmet. Secure the chin strap and you should not be able to pull the helmet off by rolling it forward over your face. You should not feel any “hot spots; that is, places anywhere on your head (but especially around the crown of your skull, where you’d wear any hat) where the helmet places too much pressure, begins to hurt, or leaves red spots. When you are trying on helmets, you should leave the one you’re looking to buy on your head, in the store, for a solid ten minutes. I know that’s a long time to wander around a motorcycle shop with a helmet on, but trust me, those are valuable minutes, and getting a helmet that fits you just right will save you money and pain down the road.

Manufacturers recommend replacing your helmet about every five years, not just because the foam can break down over time due to exposure to the elements, your head sweat and UV light, but also because helmet technology has not stalled. Five years in technology terms is a very long time, and a new helmet is going to have a lot of comfort and safety upgrades over your old one. Your head is important and you should definitely protect it.

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