How to Fit a Bicycle Helmet

Time invested in fitting a helmet pays big safety and comfort dividends!

Your objective: Snug, Level, Stable
You want the helmet to be comfortably touching the head all the way around, level and stable enough to resist even violent shakes or hard blows and stay in place. It should be as low on the head as possible to maximize side coverage, and held level on the head with the strap comfortably snug.
Be Prepared for the Worst
Heads come in many sizes and shapes. You should be prepared for the possibility that the helmet you are trying to fit may not be compatible with this particular head. And unfortunately, you should expect to spend ten to fifteen minutes to get your helmet properly fitted.
1. Adjust the fit pads or ring
Helmets that fit with pads come with at least one set of foam fitting pads, and if you got a second set of thicker pads it can be used to customize the shape. For starters, you can often remove the top pad entirely or use the thinnest ones. This lowers the helmet on the head, bringing its protection down further on the sides. It may reduce the flow of cooling air slightly, but probably not enough to notice.
Adjust the side fit pads by using thicker pads if your head is narrow and there is a space, or add thicker pads in the back for shorter heads. You may also move pads around, particularly on the "corners" in the front and rear. Leaving some gaps will improve air flow. The pads should touch your head evenly all the way around, without making the fit too tight. The pads may compress slightly over time, but not much, so do not count on that to loosen the fit. The helmet should sit level on the head, with the front just above the eyebrows, or if the rider uses glasses, just above the frame of the glasses. If you walk into a wall, the helmet should hit before your nose does!
There are also helmets on the market that use a fitting ring rather than side pads for adjustment. With these one-size-fits-all models you begin by adjusting the size of the ring. Some of them may require the ring so tight for real stability on your head that they feel binding, but loosening the ring can produce a sloppy fit, indicating that the helmet is not for you.
2. Adjust the straps
Now put the helmet on and fasten the buckle. Be sure the front is in front! You want to adjust it to the "Eye-Ear-Mouth" test developed by the Bicycle Coalition of Maine:


When you look upward the front rim should be barely visible to your eye

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