Arai helmet size chart and fit notes

Arai size chart

Arai lists sizes by head circumference. Measure around the widest part of your head, about one inch above your eyebrows and just above your ears. Our head measuring guide shows exactly where the tape goes. Not every model comes in every size, so confirm the range on the listing for the helmet you want.

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The Intermediate Oval and Arai's other shapes

Most Arai helmets, including models such as the Corsair-X, Regent-X and Classic-V, are built on an Intermediate Oval interior. That shape fits most riders in North America and Europe. Arai is unusual among premium brands in also offering a dedicated long oval model, the Signet-X, and a rounder option, the Quantum-X.

If past helmets pressed on your forehead and the back of your head, look at the Signet-X. If they squeezed your temples while leaving space at the front, try the Quantum-X. Our guide to motorcycle helmet head shapes explains how to work out your shape, and the best Arai helmets guide lists each model's shape.

How a new Arai should feel

Arai helmets tend to feel firm out of the box. The cheek pads should press against your cheeks so that when you move the helmet side to side, your skin moves with it. The crown should touch the top of your head evenly. There should be no single sharp pressure point, especially on the forehead.

Comfort liners compress somewhat during the first weeks of riding, so a helmet that is snug but painless at first is usually right. Pain within 15 to 20 minutes is not something break-in will fix. For a full fit test, follow our guide to how a motorcycle helmet should fit.

1. 1

   Put the helmet on and fasten the strap.

2. 2

   Check cheek pads press evenly and your skin moves with the shell.

3. 3

   Try to roll the helmet forward from the back. It should not come off.

4. 4

   Wear it indoors for at least 20 minutes and check for red marks.

Fine-tuning the fit

Arai interiors are removable on current models, and dealers can supply optional cheek pads in different thicknesses for many models. Thinner pads give more room around the jaw, thicker pads firm up a helmet that feels loose at the cheeks. Some Arai liners also have removable foam layers for small adjustments at the temples or crown. Check the owner's manual for your model.

Pads cannot fix a shape mismatch at the forehead. If the helmet pressure is at the front or back of the crown, change model or shape rather than size.

Glasses, intercoms and other fit factors

If you wear glasses, try the helmet with them on. Some Arai models have channels in the liner for eyeglass arms, and thinner cheek pads can also make room. Do not size up to fit glasses, since a loose helmet can shift in a crash. Our guide to motorcycle helmets with glasses has more tips.

If you plan to fit an intercom, check that the speaker pockets line up with your ears and that the speakers do not press on them. Speakers that push into your ears can feel fine at first and painful after an hour. Thin speakers or slightly thinner cheek pads can help. Hair length matters too. Measure and try the helmet with your hair the way you usually ride, since a thick ponytail or long hair under the liner can change how the helmet sits.

Between sizes and switching brands

If your measurement sits on a boundary, such as 58.5 cm, try both sizes. Many riders choose the smaller one if it is snug but pain-free, since the liner settles in. If you are moving from Shoei, compare our Shoei helmet size chart and the Shoei vs Arai comparison, because the same size letter can fit differently.

Buy from a seller with a clear return policy, keep tags on and test indoors before riding. Arai helmets are a significant purchase, and a return is easier than living with a poor fit.

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Frequently asked questions

Do Arai helmets run small? Arai helmets feel snug when new, which some riders read as small. Go by your measurement and the model's chart rather than assuming you need to size up.

What Arai fits a long oval head? The Signet-X is Arai's long oval model.

What Arai fits a round head? The Quantum-X is Arai's rounder fitting model.

Are Arai sizes the same across models? The circumference ranges are generally the same, but shape and available sizes vary by model. Check the listing for the helmet you are buying.