Originally Posted by
Coupon
That is why fit is crucial.
Yes, but even with a properly fitted helmet it's still essentially a cap on a dome. It can still rotate/pivot out of place with enough force. Mine fits me perfectly. It has the adjustment knob on the back and when I start cranking it down the helmet feels like it's attaching itself to my head. However, unless I crank down the chin strap so tight that I can't open my mouth to eat, it will still be possible for the helmet to shift under impact.