Skiing vs cycling

[Linford]

So what? I said that it doesn't matter, not that no one spends money on it. Perhaps your enthusiasm for polystyrene hats for cyclists is based on a covert economic argument? If so you can just admit it - it can't make any less sense than anything you've advanced thus far.

You mean that it doesn't matter in your world..Ah Right !

 

[Wobblers]

You mean in respect to how much force is required to move an object like a drive shaft or bolt around its Z axis....or in practical terms if it requires 1ft lb of torque to turn a nut to its required setting then the easiest way to do that would be to apply that 1lb of force to the end of a lever or fulcrum which is 1ft long.
I live in the real world mister and I solve problems on a daily basis which you might only ever read about in your books.

That's a lot of words to avoid saying "force times moment". Clearly you don't understand. Clearly you lack the mathematical intuition to understand, because you are saying that the best way to tighten a bolt to 5 Nm is to use a one metre long spanner!!!

And blethering on about "real world problems" merely serves to underscore your ignorance. It simply does not occur to you that understanding the principles involved makes practical problem solving much easier. Which is why professional engineers spend many years learning all about this book stuff you so ignorantly disparage. Fortunately, you're not an engineer.

 

[Wobblers]

Good to see you appreciate the difference between polystyrene and expanded polystyrene. I used the term (expanded poly)'styrene' as an abbreviation for the sake of the debate (just so you know for future reference)....I thought you were intelligent enough to understand what exactly I was referring too in relation to the expanded foam used in all safety headgear as they pretty much all use the same stuff for the task of energy absorption.

You are implying now that the (expanded poly)styrene will not crush before reaching its shear point now, or that the foam in the shell will not only lose all of its structural integrity as a component, but also the foam pieces once divided inside the shell will also lose all of their mechanical properties ?

Now I put it to you again....if you feel that styrene is inadequate for the task of energy absorption in impacts, what is your alternative?.... in fact you must be in the wrong business because the safety headgear industry is worth billions each year....you need to educate the manufacturers that they don't know what they are doing....why not start with HJC...they are the worlds largest lid maker and manufacture millions of them each year ?

In fact why not approach the FIA and tell them what you think....and that all their drivers should abandon the use of crash helmets because you can prove through your peer reviewed pingpong ball lab test that when you exceed the shear point of a material that it does indeed shear.

Whilst we are about it, metal is a fairly rubbish absorber of kinetic energy, but is a very good translator of it....perhaps you might try this with a newtons cradle one day ?

Your first error begins with pretending you knew the difference between styrene and polystyrene all the time. The industry standard term for expanded polystyrene is EPS. You didn't use it because you don't know it. The best practice is to simply pass over your mistakes (or, more elegantly, acknowledge them and then continue) - trying to pass them off as deliberate terms merely serves to make you look more the fool... moreover, a fool who lacks any ability to communicate...

The rest is just an information free rant. I've seen more entertaining stuff on the tin foiled conspiracy nutter sites. Why not look up a few for some tips? At least I'd give you a well earned like for being funny.

Incidentally, the plastic deformation of metal (note qualifier) absorbs a good deal of energy. Which is why we have these things called "crumple zones" in cars. Crumple zones are made of metal. They do a splendid job of absorbing impact energy. Wrong again, eh?

 

[david k]

We continue to debate this because people are either completely unaware of the facts or constantly try to dismiss or ignore the facts with opinion and anecdata over and over again - that's why they are constantly challenged and it's right to do so. We constantly hear posters spout the same old uninformed nonsense and that is harming cycling as a safe activity for all. Thankfully those you think are trying to humiliate are trying very gently, patiently and even doggedly to explain some reality in the face of often unyielding ignorance. They're doing this because it's important.
Linford (as you mentioned him) unfortunately starts to dig a hole and when faced with good reasons why he should stop digging just digs that much harder. He buries himself effectively.
Finally, there is no anti-helmet agenda here, but there is anti-compulsion.

That is your view and I respect it, I also accept others see it differently and I think they are also allowed opinion without ridicule.
I dont think this harms cycling safety to the extent some think, IMO.
Anyway, no point us discussing this as I agree to disagree, just pointing out its not only Linfords opinion

 

[Wobblers]

But even if it cracks and therefore absorbs less energy: Do i want forces from striking the sharp edge of a kerb (of rock) directly impinging on my skull or do i prefer them spread over a longer time and wider area?

A helmet that suffers catastrophic failure as this will do little to reduce acceleration conducted to the head in any form of impact.

This is a major issue for the helmet designer. It needs to be able to absorb energy, and reduce acceleration. That means you want a soft, low density foam which will absorb energy over large areas. But sharp points such as kerb stones put a lot of force into a small area. A soft foam will compress readily, and allow the kerb to directly contact the head before much energy has been absorbed. To combat this, you have to use a stiffer, higher density foam. But a high density foam transfers more forces into the head when in a collision with a flat road surface....

 

[Wobblers]

Nice try at a recovery but no prize. You got rightly spanked by The Mighty McWobble for posting bollocks about something you had clearly googled and didn't understand...

Oi! How come it's me that has to do all the work while you get all the likes!??

 

[Wobblers]

A more frequent scenario, is likely to be : 2 cars travelling at 30mph knock two cyclists off their bikes. Each cyclist's head hits the ground at some unknown speed between 30 and zero mph. which cyclist is likely to be at greater risk of head injury: Helmeted or unhelmeted?

According to the best medical evidence, neither.

 

[Wobblers]

Yeah but you got to spank the Linfy.

It just isn't the same.

 

[Fab Foodie]

That is your view and I respect it, I also accept others see it differently and I think they are also allowed opinion without ridicule.
I dont think this harms cycling safety to the extent some think, IMO.
Anyway, no point us discussing this as I agree to disagree, just pointing out its not only Linfords opinion

Having an opinion is fine, having one you can support is better, maintaining one doggedly when it clearly is not supported by evidence is fine as long as you don't keep pushing or refusing to admit what the facts support. In that situation it's hard to avoid ridicule.
Nobody cares if you (or others) wear a helmet for whatever reason, what we do care about is that people understand that there are some facts and those facts are important. There's much too much errant nonsense out there regarding the value of helmets but more importantly the safety of cycling. Some of us feel it's important to make a small stand.

 

[Linford]

Your first error begins with pretending you knew the difference between styrene and polystyrene all the time. The industry standard term for expanded polystyrene is EPS. You didn't use it because you don't know it. The best practice is to simply pass over your mistakes (or, more elegantly, acknowledge them and then continue) - trying to pass them off as deliberate terms merely serves to make you look more the fool... moreover, a fool who lacks any ability to communicate...

The rest is just an information free rant. I've seen more entertaining stuff on the tin foiled conspiracy nutter sites. Why not look up a few for some tips? At least I'd give you a well earned like for being funny.

Incidentally, the plastic deformation of metal (note qualifier) absorbs a good deal of energy. Which is why we have these things called "crumple zones" in cars. Crumple zones are made of metal. They do a splendid job of absorbing impact energy. Wrong again, eh?

These crumple zones are not solid though...they are a very small percentage metal, and a very large percentage air, and the energy doesn't get 'absorbed' by these crumple zones, it gets turned into heat as it deforms or translated into kinetic energy,which is then channeled into other structures around it.

Jeez McWobble, your ego is truly immense...now how come you don't apply it in the real wold ?

 

[mcshroom]

What do you think the 'turning into heat' means? Oh, and the energy in an impact is already kinetic energy so would need no 'translation'.

Tip - when you are in a hole, stop digging.

 

[Linford]

Having an opinion is fine, having one you can support is better, maintaining one doggedly when it clearly is not supported by evidence is fine as long as you don't keep pushing or refusing to admit what the facts support. In that situation it's hard to avoid ridicule.
Nobody cares if you (or others) wear a helmet for whatever reason, what we do care about is that people understand that there are some facts and those facts are important. There's much too much errant nonsense out there regarding the value of helmets but more importantly the safety of cycling. Some of us feel it's important to make a small stand.

Some of us feel it is important that others here understand that cycling is not risk free and it will cease to be a great pastime/mode for them if they get seriously injured doing it...because they took the advice of people spouting with their own agenda and ditched the lid.

 

[Linford]

If anyone were suggesting that cycling were risk free, you might have a point.

You are suggesting that the risks don't warrant any form of mitigation ?

 

[Linford]

That's a lot of words to avoid saying "force times moment". Clearly you don't understand. Clearly you lack the mathematical intuition to understand, because you are saying that the best way to tighten a bolt to 5 Nm is to use a one metre long spanner!!!

And blethering on about "real world problems" merely serves to underscore your ignorance. It simply does not occur to you that understanding the principles involved makes practical problem solving much easier. Which is why professional engineers spend many years learning all about this book stuff you so ignorantly disparage. Fortunately, you're not an engineer.

Don't be a fool. I was stating that it is one way of applying a measured force to achieve a specific torque. Do you have any real world experience in engineering ?

 

[ufkacbln]

It is possible to think beyond the immediate. Your grandchildren perhaps?

He's simply avoiding the obvious answer again.... as demonstrated here:

You seem to struggle with a differentiation between low risk and no risk. As a biker, I have no problem protecting my head from potential injury
The reality is that the only time you would need to wear any form of head protection would be beyond the point where you are in a position to choose one way or the other.

Lets actually try and answer a question this time?

You have clearly stated that there are some motorcycle activities where you do not wear a helmet .... is this actually the case?