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What is the head circumference for a motorcycle helmet?

2 Answers

GemmaAnn

07/28/25 7:54pm

Helmets are generally divided into sizes XS, S, M, L, and XL. Head circumference of 53～54 cm: Generally choose XS extra small size. Head circumference of 55～56 cm: Choose S small size. Head circumference of 57～58 cm: Choose M medium size. Head circumference of 59～60 cm: Choose L large size. Head circumference above 60 cm: You can choose XL extra large size. Measuring head circumference: Since everyone's head shape is different, it is necessary to measure the head shape accurately before purchasing a helmet. Measure the head size, which is the circumference from the brow bone to the back of the head. When selecting a helmet, choose one that is 2-3cm larger than your head circumference. Notes about helmets: The inside of the helmet must be equipped with impact-absorbing padding, and the surface padding material that fits the head should be made of a fine mesh lining, which should have the function of absorbing sweat and head oils. In addition, the padding should have ventilation grooves with a depth of at least 10MM to allow air circulation inside the helmet.

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MacPaige

08/12/25 12:43am

I often help friends choose motorcycle helmets, and the first step is to measure the circumference of their head. Use a soft measuring tape to wrap around the head just above the eyebrows, pull it snugly, and read the number. Adults usually measure between 55 to 62 centimeters, but it's essential to try the helmet on personally. A helmet that's too loose will wobble and may come off in an accident, posing a danger; one that's too tight can cause headaches and discomfort. It's recommended to take multiple measurements and use the average, jotting it down on paper. Size labels like S, M, and L generally correspond to 55-57 cm, 58-60 cm, and 61-63 cm, respectively. However, size ranges may vary slightly between brands like HJC or AGV, so it's best to try the helmet on and move your head around to check for stability. Measuring before buying saves trouble—safe riding starts with attention to detail. After years of riding motorcycles, I've found that an ill-fitting helmet can lead to fatigue while driving.

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