Never mind, this link explains why etc.
http://www.youtube.com/watch?v=Azvn9wPDu_c

Need to be more careful next time I ride in t shirt and shorts!

Never ever ride in tshirt and shorts! I look at people doing that and think "knob ends... they are gonna smart when they come off! - IF they don't kill themselves!"

The worst ones are the 16 year olds that have t-shirt, shorts and trainers, and then go weaving round the traffic, and riding 2cms behind your bumper.

I think if one of these idiots crashed into the back of me and came off for being too close I would get out of the car, kick him, and drive off!

None taken bud, I had a bad mountain bike crash a few year ago and it was a lid that saved me from more serious injury. I know that aint as quick as a motorbike but i was downhilling through a wooded section when a large oak tree stopped me dead! Probably why i went into forestry lol.
As far as i'm aware through health and safety you not even meant to use a marker pen on helmets for the same reason as stickers, must be the chemicals used.

I have actually had that happen to me. Was driving home one day when had to stop at traffic lights when this little bee in a biscuit tin crashed into the back of me. The chavvy family asked if they could pay for the work to be done rather than go through insurance, then tried to argue the quote down. So I told 'em to get f**ked and telephoned insurance company in front of them. Knob ends :slap:

Ive only ridden a few times in t shirt when its extremely hot and not going far. Usually have a jacket on :)
Its the ones who ride on superbikes at 100mph plus in t shirts that I worry about.