Another pea head checking in. I too can wear a childs or youth sized helmet - I just can't bring myself to wear Barney on my helmet. I have in the past worn a WSD Giro and the fit was pretty good although I did have to add some foam here and there. Since, I have worn the Trek WSD and currently have a Trek Anthem Elite (obviously size small). This is the first helmet that I was able to wear without the extra padding added. Even the strap was adjusted perfectly for me .