meanwhile

This just shows that you still don't understand how helmets work: the amount of energy need to reach a helmet's MAXIMUM limit is tiny: it's the energy that your head alone will have if you fall of your bike while cycling at about 0-4mph - a 12mph impact velocity. So the bottom is very low - you'd have to in a recumbent to get beneath the maximum! So to go beneath the minimum I'd guess you'd need to be lying on a skateboard - it's a figure so low that it never gets discussed.

Please stop posting until you actually read the helmet specs, yes?

MMACH 5

So, you're saying that EVERY time a rider falls, they exceed the maximum ability for the liner to absorb energy? If that was the case, then every helmet involved in a crash would be cracked. Thus, every time a cyclocross rider or MTB racer hit a tree or the ground, the helmet would essentially be destroyed. While the helmet specs call for it to be replaced after every accident, we've all seen that most helmets remain in tact, after a fall.
A person would have to be riding a REALLY tall bicycle to exceed the height at which helmets are tested.

And your math is a little skewed. You keep mentioning 12 mph as an impact velocity of testing helmets. An object falling 6 feet will reach a velocity of just over 14 mph (6 feet is the height of the testing apparatus). Not a huge difference, but it is 15% off. I'll refrain from asking you to stop posting until you actually do the math.

350htrr

Yes, the numbers could certainly be skewed, that is why I mentioned that it would also be good to know how many were wearing a helmet or not, in the total 50,000 people that went to the ER with head injuries, it also would be good to know how many died from internal in juries but are under the head in jury deaths. But you are speculating too as to how many risk takers are in what group they ended up dead in... There is A HUGE DIFFERENCE between 70% and 12%... I think I do have the intelligence but maybe not the edumacation...

mconlonx

Yeah, I finally sat down and read it last week, meant to find your post, but it's back a ways now...

Decent article. Like I said previously when Bicycle Times published two articles, one helmeteer view/one bare-head brigade view, it's getting to the point that the helmet nay-sayers won't be able to say they're not getting fair press. Much of the incorrect and improper helmet scare-mongering seems to be diminishing as well.

meanwhile

No. But I can understand why someone who was entirely ignorant of physics - even high school physics - would think that. What matters (theoretically at least) is only the velocity of the helmet perpendicular to the surface it strikes - if you have a forwards velocity of 30mph then **in theory** that doesn't matter. In practice, helmets often shred at this speed because of abrasion.

Once again: please understand at least the very BASICS before posting! This stuff is covered in the sources I have given.

If you think that a regular helmet is going to survive a +20mph collision with a tree, then you have missed the reason why downhill helmets weigh a kilo and cost $600!

I haven't seen that, and I wouldn't take your word for it. However it could happen for a reason that is obvious to anyone smarter than you - in reality, the arms protect the head in low speed hits and head contact is rare. So sometimes a helmet will just "kiss" the ground without taking any real energy.

No, they'd just have to fall so that minute part of bodyweight was taken by the helmet. Or if the helmet hits a non-horizontal surface - even the edge of a cobble stone - then that's out of the spec because horizontal velocity is engaged. In fact, any road surface that is not smooth is out of the scope of testing.

12mph is the figure the Department of Trade And Industry cite and I am in the UK (hint - spelling, the sources I've used?). If you'd paid attention you'd know that.

It must be horrible to be want to be smug, but have nothing to be smug about...

meanwhile

Once again, there is a huge difference between 70 and 12%. Well done! You may soon be ready for arithmetic! But once again, it is stupid to assume that the difference exists because of helmets rather than behaviour. Because the difference is much the same as between the 80% fatal accident rate for men and the 20% rate for women. Which - and again, some of reasonable intelligence would already have got this point - means that either

1. You are a very silly man indeed, and behaviour really can make that bigger difference

2. Breasts are at least as good as bicycle helmets in preventing head injuries. (Or maybe ovaries? But that seems even less likely..)

And I'm afraid the smart money is not on the breasts...

Notes for anyone of reasonable intelligence:

i. about 48% of adult accidents are incurred by YOUNG men, so applying 350 "logic" you'd also have to assume that baldness and other aging symptoms cushion impacts with SUVs...

ii. Remember that 95% of non-helmet wearers who die HAVE FATAL TORSO INJURIES... Which helmets can't protect against, yes?

iii. In fact, in cities where wearing a helmet becomes standard, eg because of mhls, THERE IS NO REDUCTION IN RISK. Which proves that it is behavior, not the helmet that counts - because if it was the helmet (and it is idiotic that I need to spell this out) then you WOULD see a reduction.

MMACH 5

Clearly, I was responding to your comment about a helmet's maximum and minimum limits of compression and energy dissipation. You had made no mention of abrasion. You had made no mention of downhill helmets. You chose to now insert other arguments.

And here I thought the UK had switched over to the metric system. Unless they have and you chose to use the non-metric MPH instead of KPH. Makes for a convenient opportunity to then accuse a reader of not paying attention.

meanwhile

Well, yes - but again, you're wrong about a lot of things. UK road signs are still in miles and mph, and people still usually give their weight in lbs - or more commonly stones and pounds - and their height in feet and inches.

Yes: the entire UK government and population are conspiring to make you look bad. No, you are not crazy!

buzzman

The following post is from a moderator in this thread on May 30th:


This is a post in this thread from two hours ago:

Someone has issues with reading comprehension.

Dare I say it but "it is idiotic that I need to spell this out"

350htrr

Or, it could mean that 80% of bike riders are men and 20% are women thus the accident rate of 80/20. i. Don't really understand what you mean, but one would expect a higher accident rate for young men if risky behavior is sooo rampant and causses those high death numbers in the un-helmetted. ii. 95% of the helmet wearers could have also died from fatal torso injuries thus the wide gap/difference in the death numbers of helmetless & helmeted would still exist. iii. There is a helmet law here and it seems like 50% of the people don't wear one so statistics wouldn't change here. iii.

mconlonx

Meanwhile trying to explain things to 350htrr is music to my eyes...

meanwhile

Given that I posted at least once that I was using figures from NYC, where men and women put in about equal miles and have equal rates of helmet wearing, no, it could not mean that. Read the posts you respond to. If you are too lazy to read back a page in an extended thread, then ask questions - or google - rather than assuming.

This I can believe..

Yes, one would. Except that you miss the truth that "rampant" is inappropriate - because cycling deaths are actually VERY rare, and so a small number of people in a group like "young male" or "non-helmet wearer" can have a huge effect.

Wrong. The point - which is fairly obvious - is that if 95% of non-helmet wearers die from torso injuries, then wearing a helmet would make at most a 5% difference to that group. Therefore, the difference between the non-helmet group and helmeted is behavioural if its is over 5%; anything else is mathematically impossible. That 95% of helmet wearers would also die from torso injuries is true but irrelevant. This is called a "plausibility test" and you just failed Remedial Introductory Science...

Look: can I suggest that if you are arguing with people who are professional engineers, scientists, and statisticians, and that they tell you that your understanding of basic scientific method, logic, and statistics is completly non-existent - that it isn't even at the level a bright 12 year old could work out for himself - that you give serious consideration to actually looking up stuff like "argument by conclusion", "ecological fallacy", "correlation vs causation", "sampling bias", etc, before trying to take on the entire edifice of western science based on your own unique genius??? That, and actually following the thread well enough so that you know what was on, oh, the last two pages???

Jseis 

Couple comments:

After posting a few comments I realized I knew zip about helmet tech, tests, etc. So I'm informing myself.

I started reading all pages of the this helmet thread from the beginning to find missed links, gauge the tone between posters and gauge if anybody learned anything though I'm particularly interested in repeat posters guarding their POV. As a consequence of crawling through page after page........I've realized that primary data links are somewhat rare while links to various analysis & opinion regarding interpretation of primary data are pretty common. Drill deep enough and you'll find the primary authors of data arguing at each other....Particularly around data sets, statistics. I'll post primary data analysis I run across (some may be reposts). Some are pay wall guarded. Some aren't. I'm most interested in helmet testing data.

Here's an interesting one. Note the rough pavement pic...and the author's comment about how they protested their expensive test dummy's "face". Also note the cost of the test.

https://www.helmets.org/hodgstud.htm

Also...here's a great link for calculating speed at impact from a known height (not the average velocity but the instantaneous velocity). Also energy based on mass. Called the Splat calculator and devised by climbers. If your curious how fast your instantaneous velocity is from a fall and how much energy......you get the picture.

https://www.angio.net/personal/climb/speed

Finally. If the name calling continues I'm sending PM's to the Administrators and recommending those individuals get booted off. Calling people "stupid" in particular but any name calling is simply not called for.

Cheers.

350htrr

Well meanwhile, if you can postulate that 95% of the helmet-less deaths were caused by non head injuries, I can postulate that 95% of the helmeted deaths could have been caused by other than head in juries too... So that leaves 21 helmet-less dead /4 helmeted dead per year... That's still 5X+ more deaths... And no I didn't look up the word postulate. Any brownie point for that?

meanwhile

I don't "postulate" that: it's a fact that I sourced in the last few pages.

Yes. They would certainly would be.

Yes, no one disputes this. The problem here is that you are not smart enough to understand what you are actually being told, even after repeated and increasingly dumbed down explanations. Which is that

1. Either the cause is that helmets prevent deaths and explain the difference

2. Or the difference is due to the behaviour of some people in each group

Now, as 95% of the deaths that make up the difference include fatal torso injuries, Option 1 is impossible. Helmets do not prevent torso injuries, so if you replayed all the helmetless accidents then, AT MOST, only 5% would be made non-fatal. Therefore Option 2 is the only possible one. (Which makes sense, because far fewer women engage in high risk behaviour than men, and in NYC women were 8 to 9 times less likely than men per mile to suffer a fatal accident.) To me this seems very simple understand. But to you this seems to be on the other side of some impossible barrier of intellectual attainment, liking learning quantum mechanics in Chinese...

The only way this logic would not work is if helmets prevented torso injuries, which I think we can agree is silly. You probably still don't understand this logic, but trust me, it's pretty basic science.

Oh well - at least you have worked out to use the smiley menu!

MMACH 5

meanwhile, in your mention of the NYC cycling stats, you say that the miles ridden by men and women is roughly equal.

Here's a NY Times article says, "Male cyclists in New York continue to outnumber female cyclists three to one..."
This has to skew the stats on the count of cyclists involved in accidents with breasts. Unless, of course women in NYC ride 75% more miles than the men, on average. That would bring their miles covered closer to your claim.

https://www.nytimes.com/2011/07/04/ny...a-concern.html

350htrr

I have never said helmets will save your life, what I have said/tried to say is that wearing a helmet is better than not wearing a helmet when your head actually bounces off the pavement, and even when death is counted, there seems to be 5X higher number without helmets as with helmets which even I agree that helmets basically fail at miserably but those numbers show that helmets still effect the death ratio somehow... Even way back in post 4487 I never thought a helmet would save my life... https://www.bikeforums.net/showthread...-thread/page41 Arguing about a helmet saving lives is the tip of the iceberg, The real meat of this discussion should be how much did the helmet help or not help those 49,000 people who went to ER last year with head injuries...

Siu Blue Wind

*sigh* Thank you for participating.

350htrr

Hey, meanwhile, and some of you other helmet-less guys, I know I am not as edumacatted as most of you , but... I have worked in an industry for the last 40+ years that relies on "statistical info" and actual "measurable" info, to "get the job done safely"... And... I can assure you, over the last 40+ years I have had my "run-ins" with ENGENEERES" with much more education than me, that just had everything figured out, but I came along and said, about a dozen times in 40+ years, well it "can" be done, but... Everyone of those engineers but 2 of them went along with my idea on how it can/should be done safely in the "real world" and things worked out... But I got fired on those 2 occasions where I told the "engineers" and they didn't agree that maybe it's not the way to do it safely, but I was dramatically proven right on both of them. What would have happened on the others, I don't know... Things on paper are not as solid as some would like to think, things in real life often don't follow "lab test protocols" My point here is/trying to be, that road apples happen all the time, sometimes you need to be prepared or you step on them, so you need to follow your little "inner" voice, if it says wear a helmet it could "save" your life, wear one. If it doesn't say that, well...

Six jours

Short version: "I do what my voices tell me to do, even when those voices are contradicted by people who actually know something about a particular topic. Moreover, you should do what my voices tell you to do too. If you don't, you'll suffer well-deserved injury."

Six jours

Good for you. If you actually come into this with an open mind, you'll find very little hard science (and what there is of it is often murky, if not outright contradictory) and quite a bit of politicking.

You also note a great deal of antagonism toward the "I wear a helmet because I care about my brain" attitude that is so common with our ranks. You might bear that in mind: there are very few actual "anti-helmet" people, but a great many "stop preaching and leave me alone" people. There obviously are a few hot-heads on both sides of the issue, but a great deal of the antagonism stems from the smug ignorance of the helmet crowd.

350htrr

Ha, Ha. that's funny. Are you an engineer? I better line my helmet with tin foil. What frequency are you going to send out those evil thoughts at...?

sudo bike

In short: no. Becomes more and more clear you don't understand what it means at all.

Shifting the goalposts doesn't occur every time the issue being discussed changes... conversations wouldn't get very far if that were the case. We'd all be stuck talking about the one topic we all started talking about. Shifting goalposts (for the billionth time) is when you make a point and then change it when a counter-point is made to avoid addressing the criticism. That isn't what was done. Here, I'll go over it with you so you can learn:

As you can see, I actually was addressing his point and the fact that the logic he was relying on could be used to advocate any manner of silly levels of safety equipment, not dodging it at all. He retorted to that point that body armor is a silly level of safety compared to a helmet because it only protects against mostly superficial injuries like road rash, while helmets do protect against more fatal injuries, since head injuries kill more people. I responded that, on the contrary, bodily injury is just as likely to kill you, so to be logically consistent, you should be wearing body armor as well if the goal is to have safety equipment (however inadequate) covering parts that are likely to contribute to death in a crash. You following?

So, if I was shifting the goalposts, you should be able to point out a) what point I was making, b) what robble's response to that point was, and c) how did I change the goal to dodge that criticism. I expect a 2 page essay, double spaced, on my desk by Monday.

You can't, right? Then it isn't shifting goalposts.

Actually, the argument was made you probably shouldn't wear a helmet if your goal is to protect your brain. If your goal is to mitigate minor injury, tally-ho.

Is only a single aspect of helmets on for discussion? How do we change discussion from one aspect to another without engaging in your definition of "shifting"?

Like I said: high school never gets old, does it?

sudo bike

See, this is how I know that despite your protests, you haven't a clue what shifting goalposts is.

I even said back then, and will repeat here: shifting goalposts isn't merely changing the subject. It is very specifically changing the point you first made to dodge a critique, often in a subtle way. You don't get to just declare other subjects off-limits because of the fact it shows huge logical gaps that are inconvenient for you, sorry. That isn't how it works

sudo bike

Tell me about it. It's like trying to nail jello to a tree.