I've never worn the 1/2 helmets, but I've had a problem with glasses shaking even with my 3/4. I just got new glasses and went for a ride the other day, and the glasses didn't shake nearly as bad as before - my guess is the frames are tighter on these than on my old ones. Maybe you could try a new pair of glasses and see if that works for you too. Good luck - I know how annoying that is!! :yes: