Nov 24, 2007

Motorcycle Helmets: What is a retention mechanism? What does it do? How to take care of it?

In most cases, helmets use two kinds of retention mechanisms. The one more common in Indian helmets is the quick release buckle (QRB). Which is essentially the same mechanism that secures your three-point seatbelt in the car. A little sewing machine oil now and then is about all it needs. And if you did oil your QRB, you're obsessive-complusive. Even I don't do that. QRBs are easier to use than the other type of mechanism, but the tightness cannot be adjusted on the fly. You usually have to take the lid off and fidget a fair bit to tighten or loosen the straps.

The other, and probably the better mechanism is the Double D-Ring (DDR), which is the de facto standard in all 'serious' helmets. The reason why DDRs are considered better is because it isn't possible to loosely fasten a DDR. It has to be snug. Why is snug important? I'll tell you in a minute. DDRs are a little more fiddly to use than QRBs. But again, my experience says it's matter of getting used to and within a couple of days you will not notice any difference in ease of use. The DDR is usually equipped with a small catch that secures the loose end and stops it from flapping around.

Most helmet standards require that the helmet retention mechanism, specifically, the nylon straps that host the QRB or DDRs, are not attached directly to the shell itself. Usually, a metal ring (usually a triangle) is attached to the shell and the nylon strap is stitched to this ring. I don't fully comprehend why this should be, but there it is. Further, in most cases, the nylon strap is lined with a softer material to prevent chafing skin.

Open face helmets, or jet helmets may sometimes have a chip cups incorporated in their retention straps, usually with a QRB.

Related links in this series:
Other links on helmets

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