World Track Cycling Championships on the Box Tonight

Ant I thought a helmet was optional but if worn must conform to some standard or other. The aeroness of my head is the least of my worries though to be honest :)

Like I said, it depends on who's checking the rules. World Cups, Champs, etc. are UCI events so you have to comply with their rules. Riding a High Wycombe 10mi, you'll probably not be questioned about your lid.