Had a Robin bounce of my helmet at about 80mph while on the bike one day, felt like someone tossed a bowling ball at me!
I have no idea how I managed to not crash as I was definately seeing stars for a couple of seconds
. There was a huge chip in the helmet from where the beak(I assume) hit right on the forehead above the visor . the visor was also cracked, this is the main reason you will never catch me wearing anything but a fullface helmet.
Have a good one,
Dan