On 27/10/12 08:18, Phil W Lee wrote:
James considered Fri, 26 Oct 2012 16:26:01
+1100 the perfect time to write:

On 26/10/12 16:06, Frank Krygowski wrote:
(Helmets do nothing against rotational
acceleration, and may even exacerbate it.)

Got data?

I've heard helmets are supposed to offer more grip of the road surface
than hair/skin/flesh/bone, but never seen the test results.

Also greater leverage, due to the increased diameter.
And increased risk of contacting the road in the first place - human
reflexes are actually quite good at protecting the head, but do get
beaten by increases in effective size.
It's a bit like running the hurdles with clown shoes on - even the
best hurdler would expect to clatter a few with that kind of handicap.


As I said in a previous reply, I've never damaged a helmet in any
bicycling accident, though I've always worn one and been in numerous
racing accidents and a few training accidents - some of which involved cars.

--
JS