[QUOTE=slvoid]Is this on a per mile basis? per rider? per sheer mass? (Prove you right?)

like I said before, an objective judgement about relative risk. Something like, 10% of motorists were admitted to hospital with head injuries and 10% of cyclists were admitted admitted to hospital with head injuries.

Look it up. I found most activities have a similar rate, just under 10% with small variations. I could be wrong.

All these head trama stories are terrible, but head trama happens to everyone and not just on bikes or more often on bikes. Wear a helmet if you want, fine, just don't say you're not going to have a head injury that could have been prevented by a helmet when you get off the bike.