Biking without a helmet (Page 3)

x2. Going on six weeks now and still recovering. Helmet was cracked both front and back. Minor concussion from the impact, and I was only going 18mph. There is no doubt that without a helmet I'd be in far worse shape.

The major difference with being hit by a car is the weight and speed of the car. Although given that its pretty hard to get hit in the head by a car, and it's the impact with the ground that causes brain trauma, I still believe a helmet would provide some protection.

You live in the SF Bay area? Isn't it pretty hilly out there? I would not bike to work if I had to go up the hills in SF, at least judging by what I've seen on visits out there.

A fall from a height of 6 feet will be 13.36 MPH. You were going 18 mph and suffered a mild concussion. Your helmet did what it was intended to do. The 5 mph that you experienced was manageable and did not result in a severe injury.

When people say "without my helmet, I would be in much worse shape"... well we can guess, but we don't actually know. And moments of impact can be a huge range of factors involving glancing blows, decelerations before impact, how you hit or how you braced.... all we can guess is these were the factors before the incident, and after my helmet was cracked.

I'm not at all arguing that bicycle helmets do not offer any protection. Indeed the protection they do offer is well tested and if I am going to be involved in any accident I want any energy attenuation I can get. I'm just saying, the level of protection they do offer is well below what people think they offer and indeed use them for.

Even look at the TDF... they mandated helmets finally after the death on the decent where Casartelli hit his head on a barrier doing around 50mph... that same crash today with a helmet will still result in severe head trauma if not death.

I got in the habit from MTBing and worrying about the worst case scenario... falling backwards and hitting my head. I have never put a scratch on any helmet I have owned. A friend hit his forehead on a endo at a stop. We did not realize his helmet was cracked and head was bleeding. He had a pretty bad headache and was done for the day. Mild concussion from a slow speed bump on the head with a helmet.... which most certainly prevented a much worse concussion. It just depends.

I love it v^2=u^2+2as.

Yep, it surely does depend. There was a rider in PA who died wearing a helmet and he was barely even moving. Just happened to get tapped waiting for an event to start, fell backwards, and struck his head just below the helmet. And I amend my statement to say I *believe* it would have been worse. I lead with my face, and have the scars to prove it, and still managed to do a flip and end up on my back 

Ya, bizarre. Helmets do attenuate energy. That is it's job. And it most certainly did in your case, and it does in cases where we see the helmet deformed and broke. I wear a helmet. I have for as long as I have been riding. MTBing you never know what strange position you may end up in or what will reach out and touch you. Riding on the road I just feel naked. I do not fear some strange crash position, even though anything is possible. And I have no illusion that a high speed impact from a car will not result in serious injury and probably a head trauma. Bones heal, and I will take a severe concussion over a coma any day if given the choice. But when we reach energy levels involved in a car/bike collision... all bets are off. Every single manufacturer and standard agency will tell you that is outside the scope of the design.