Remember kids... always wear a helmet. (The almighty bikeradar helmet thread)

Modern helmet design means that your head is ~1.5 degrees cooler than if you are not wearing a helmet*, and the Kamm tail design means that you are also more aerodynamic with a helmet than without.

The two things are not both true for any one helmet design. Some road helmets are cooler than bare head, some TT helmets are more aero than bare head. So far, there isn't one which both keeps you cool and makes you faster.

@Eightball

Buffallo Bill posted something earlier today that led to this
http://www.thecochranelibrary.com/userfiles/ccoch/file/Safety_on_the_road/CD001855.pdf

anecdotally I have had head road rash at an off at plus 40kph and tinnitus after a motorcycle rode into the back of me at around 15kph - two head related injuries in twenty years of riding including eight years as a messenger

I haven't trawled though this whole thread so someone might have mentioned already that August 'Which' has a review of helmets for anyone who is wavering.. After many thousands of miles I bought one about eight months ago (Giro Savant) due to reading many ill-infomed coroners reports. I don't want my family to miss out on the insurance, even though I'm pretty sure it will not be a head injury that does me in. I have only ever banged my head once - on a wayward pedestrian in Battersea High Street, so they should have been wearing one as well. I only took it out of the box on Thursday because of ******* Bradley. I haven't worn it yet though.. Feeling nervous. I have always been a fan of Dr Ian Walker who found that cars passed him much closer when he was wearing a helmet, unless it had a blonde wig attached.

Then wear a blonde wigs with your helmet.

Ok, only I'll have to rig one up with some yellow wool due to being short of funds because of shelling out for this helmet.

Appears to be a very common misunderstanding about the often quoted 12mph impact speed helmets are supposedly reliable for. The velocity with which your head might hit the ground has nothing to do with the speed you're doing at the time, be it 5 or 50mph.

Indeed. An object dropped from a height of 1.8m will hit the ground at (9.8*1.8)^0.5 m/s =~ 4.2m/s =~ 9.4mph.

In most accidents/falls the horizontal component of the velocity won't increase the magnitude of the primary impact of head (helmet or not) and ground at all; it does cause extra slidy tarmac/gravel pain though but that's a whole different kettle of badgers and much less likely to cause a KSI.

Pedestrians falling over will have their head fall from roughly the same height which is why you might see a greater reduction in (sheer numbers of) KSIs from compulsory pedestrian helmet use (risk homeostasis and other negative factors aside - the same arguments against compulsion apply to pedestrians as to cyclists).

Impacts with other objects (other people, vehicles, being hit by a wing mirror, etc) and my first paragraph doesn't apply. Hitting the side of a van at 30mph is going to result in a bigger impact than hitting it at 5mph obviously. Hitting the bonnet of a car and going ballistic is another case where the physics gets more complicated and the impact will depend, to some degree, on the speed you were traveling.

Are you explicitly saying [because all your posts on this load of tosh suggest you are] that the Cycle training bods recommend you wear headphones all the time?

No BDW!
Cycle training Bods say utilise all your senses and know that the most reliable sense is seeing since you cannot rely on gearing to judge speed and distance nor hear silent vehicles like cycles.

Perhaps the cycle trainer myth comes from the idea that a cycle trainer training method (recommended in a certain iconic cycle training instructor manual) is that a way to test and improve looking back more is to ride without hearing using a sony walkman.

Couple having sex.
He says to her baby ill just get the condoms, let's try the Olympic.gold type.

She says, ah, honey can you get the silver one come second for once.

...and riding with an ipod is not as dangerous as listening to music in a car perhaps
http://rideons.wordpress.com/2012/07/09/an-ear-on-the-traffic/

Great day 4 hours track coaching today, back with the serious stuff tomoz.
Night

Why does he tell her baby he's getting condoms?

Cycle training Bods say utilise all your senses and know that the most reliable sense is seeing since you cannot rely on gearing to judge speed and distance nor hear silent vehicles like cycles.

This is why fixed wheel is better.

...and riding with an ipod is not as dangerous as listening to music in a car perhaps
http://rideons.wordpress.com/2012/07/09/an-ear-on-the-traffic/

Depends on how you define danger, does it not?

Person in a car listening to very loud music, pulls out without looking, car in the right hand lane crashes into the back of them.

Airbags deploy, crumple zones crumple etc, driver is fine.

So, little to no "danger".

Person on bike happily shooting along with headphones on, say they are listening to music at the same volume as a car driver, pull out without looking and get hit- that's them seriously injured.

Lots of danger.

Depends on how you define danger, does it not?

.

I define dangerous as something able/likely to cause harm...like car drivers and dangerous animals.

Benign things like people on bikes would struggle to case damage

Perhaps you could choose a word that doesn't mean both in a condition to cause danger, and in a position to cause danger.

By Skydancers definition riding with head phones on becomes an act of self harm I think.

^^If you're listening to The Smiths, then yes.

Not if you look around enough
And drivers look out for you

This is why fixed wheel is better.

you having one of your 'special' days Edbert?

better than what?

Broken wheel.

No BDW!
.... you cannot rely on gearing to judge speed and distance nor hear silent vehicles like cycles.

....

My typo and a joke from Ed

...and riding with an ipod is not as dangerous as listening to music in a car perhaps
http://rideons.wordpress.com/2012/07/09/an-ear-on-the-traffic/

As a cyclist, I think this is another case of some cyclists wanting to have their cake and eat it. The more that happens, the more infuriating some cyclists and motorists will find cyclists in general.

It's not sensible to listen to music while riding. Most occasions you see it happen on what are probably commutes. Anybody can do without music for a short distance. If you're listening to it on a low volume, then there's not much point to it. Hearing what's around you is vital. It's all part of instinct and reflexes.

There's a good reason why it's illegal to drive while using a phone - you're not in full control. A person riding while listening to music is also not in full control, and that which impairs it offers no counter-benefit whatsoever.

There's a good reason why it's illegal to drive while using a phone - you're not in full control. A person riding while listening to music is also not in full control.

That's two very different thing.

One is communicating, the other is listening.

I think it is a personal decision based on your own risk assessment. Live and let live.
Riding to beats is sometimes transcendental

...and riding with an ipod is not as dangerous as listening to music in a car perhaps
http://rideons.wordpress.com/2012/07/09/an-ear-on-the-traffic/
But there's nothing in that article that mentions danger at all (other than a link to a website discussing safe decibel levels for your hearing itself).

Where do you get this conclusion about riding with an ipod being less dangerous than listening to music in a car?