John Scalzi talks about motorcycle helmets in Some People a Helmet Wouldn’t Help :
You know what? If someone believes they shouldn’t have to wear a motorcycle helmet because the accident is someone else’s fault, the fact is I don’t want that person to wear a helmet. Because that person is clearly too damn stupid to live. For the rest of you, I’ll merely remind you of what you no doubt already know, which is that your brains will splatter themselves across the pavement just as readily when the accident is someone else’s fault as they will when it is yours.
If you’re into riding two-wheelers, this is a post you might want to read.