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Discussion Starter #1 (Edited)
I recently got into a dece discussion about why you shouldn't trash your lid simply because it slipped out of your hand. Everybody was saying "it's junk" and were also saying "everybody is saying the same thing, except oicdn, so make your own decision..."

Yes, to eliminate ANY possibility, you should replace it, but for the sake of saying "it's trash..." I refuted it, and here's what I came to..cut/pasted from my post:

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Even a completely wrecked helmet is 10 times better than nothing but for the safety of your melon you should replace it soon as you have the money for it

Exatly. It's not like the helmet is going to fail miserably if you take a spill just because you dropped it. The helmet was designed to crash SEVERELY. A simple drop isn't going to affect anything.

I think people just take things to an extreme, and take word as gospel all too much.

You want an example as to why I think if you drop it it's toast it's BS?

Look at bicycle road racing helmets. They're made of nothing more than dense styrofoam. Literally nothing else. Wait, you have a paper-thin plastic colored shell....to cover the styro and make it look pretty. It really has no other function.

-- According to data from the Motorcycle Safety Foundation:

In motorcycle related accidents, the median pre-crash speed is 29.8 mph, and the median crash speed is 21.5 mph.


That said, most road bicyclists travel at speeds ~27mph, and depending if you're a sprinter or not, it can be at speeds of up to 50 MPH+ if it's on a decent... And whenever a person wrecks on a road bike, it's usually at full speed ahead....around 27MPH+ either from a gravel spill, or collision with another biker or object.

Being the helmet is ONLY dense styrofoam, it protects the head well enough in a 50 mph crash. Now, do you SERIOUSLY think a MOTORCYCLE helmet, consisting of padding, DENSER AND MORE styrofoam, and a poly shell either of carbon fiber or fiberglass will fail simply because it fell out of your hand or off the table? Fiberglass and carbbon alone absorb alot of the impact. Think surfboards surviving huge waves in Hawaii. And they have MUCH LESS glass and foam(not to mention sparser) than a helmet. Those helmets are rigourously tested and researched with MUCH MUCH higher impact and resistance ratings than a bicycle helmet EVER will.

DH racers use pretty much a moto cross helmet. It's full face and has a poly shell with no shield They wreck at speeds of 30-50 PH constantly. Thier heads bang on trees, limbs, gravel, anything else on a DH trail. Hell they won't even wreck and thier heads take small impacts from branches and other things around headlevel. They don't replace the helmet after every race, unless they're sponsored, then they just ask for another one because they can. nowhere near the protection of a motorcycle helmet.


And if you want to take a scientific approach to it.....


Velocity = Gravity x Time

and

Distance = 1/2 x Gravity x Time(squared)

Gravity at 1 second draws an object 32 ft/sec.

So....you're looking at:

Distance = 1/2(32 x 1) = 16 feet

16 feet per second translated to MPH is

Feet per second to convert to miles per hour = feet per second x 0.6818

16 x .68 = 10.88 MPH

And that's if your helmet were 16 feet in the air because it fell for one second remember? so, if it fell from your hand, we'll say 2 feet. Thaty's 1/8 the distance. So we won't account for acceleration and just simplify and say:

2 x .68 = 1.36

or

10.88 / 8 = 1.36

Your helmet was going 1.36 MPH when it "collided" with the ground....give or take a MPH...so, a helmet designed to take large impacts, you're not going to trust it after 1 MPH???

So take that information, instead of just "the manufacturer says" and make your own decision.

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Heh, whatcha think? Don't hold back, lol.
 

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oicdn said:
The helmet was designed to crash SEVERELY. A simple drop isn't going to affect anything.

I have to disagree, the helmet was designed to absorb impact. It does so largely by compressing the styrofoam which makes up the majority of the interior of the helmet. Once its compressed, thats it. If you should take a serious impact in the same area, the only thing that will compress is your head.

I did a face plant at over 50mph a few years back, and thank god I was wearing a good full face helmet, but it went in the garbage immediatley afterward.

I have had too many friends and family die or live the rest of their days SEVERLY RETARDED from motorcycle accidents, largely on account of faulty, old, or less than perfect helmets. Why take the chance?
 

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Discussion Starter #5
Oh don't get me wrong, I'de replace my helmet after one wreck as well. But you get rocks flung at your helmet with more impact from just riding around...people don't replace thier helmets from a rock knick.

You bang your head on stuff just walking around harder than that of your helmet hitting the ground from it falling out of your hands, is my point.
 

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Arai will x-ray your helmet for a minimal charge to see if if needs to be replaced or not. Of course, I assume they will only do this for their own helmets, and I have not heard of any other manuf. offering this.
 

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oicdn said:
Oh don't get me wrong, I'de replace my helmet after one wreck as well. But you get rocks flung at your helmet with more impact from just riding around...people don't replace thier helmets from a rock knick.

You bang your head on stuff just walking around harder than that of your helmet hitting the ground from it falling out of your hands, is my point.
I see your point, and understand. I treat my helmets like infants, I am very careful with them and have yet to drop one of them. If and when I do drop one, maybe I will keep it, but as for now, I dont like the idea.
 

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Discussion Starter #11
Exactly.....I treat mine with uber care, and yeah, I would definitly replace it after an accident...but I think some people just take things a little too extreme on some ends of the spectrum....
 

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Modern helmets are made with advance composite materials so there is quite a bit of designed resiliency as far as the shell is concern. But you don't want to weakened the shell with a drop because the very next time you decided to really test your helmet against the pavement your head might not take to it too well. With that said, to replace or not to replace depends on your level of risk aversion.

Everytime you wash your liner, check on the foam. If there is indentation that compressed the foam 1/2 way (ie., thickness), I would suggest replacement. The thickness of this foam will determine the severity of your head trauma (ie., concussion mostly) during an accident. Not being able to remember things for an 8 hour time block is not fun. :)
 

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Discussion Starter #13
^^ Yikes...sounds like you're speaking from experiance. :0

Did the memory come back suddenly, or was it a slow recollection over and 8 hour time? Sounds scary as hell either way...
 

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ARCHILLE said:
Not being able to remember things for an 8 hour time block is not fun. :)
You think that is bad, try answering the same repetative question for eight hours! :blah: :blah: :blah:


If there is nothing inside the helmet when it is dropped there is nothing to compress the styrofoam which is critical for energy absorption. The composite shell should be able to withstand the average fall. Even if the shell momentarily deforms due to the impact the styrofoam will move also then return to its original position. You need an applied force and a reactionary force to crush the styrofoam.
 

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oicdn said:
^^ Yikes...sounds like you're speaking from experiance. :0

Did the memory come back suddenly, or was it a slow recollection over and 8 hour time? Sounds scary as hell either way...
Never did came back. It would have been nice to be able to recall the events that lead to the impact.
 

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I always save my wrecked helmets for any potential passengers...anyone not knowing better than to get on the back of a sport bike will not know anything about helmet replacement theory. :naughty:
 

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lewdog998 said:
I always save my wrecked helmets for any potential passengers...anyone not knowing better than to get on the back of a sport bike will not know anything about helmet replacement theory. :naughty:

:laughing: :laughing:


But isn't the crack and asphalt scrape a bit of a giveaway? :laughing:
 

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ARCHILLE said:
Never did came back. It would have been nice to be able to recall the events that lead to the impact.

8 hours is long! scary.

I had a 15-20 minute 'gap' from a snowboarding accident (ran into a skier who was going to slow.... :stopp: ) I was asking the same thing over and over again "what happened"..."did you see it"..... was moving around, etc. people took pics of me with my own camera. don't remember shit.

It was the first time that year that I actually wore a helmet.... damn glad i did that.

Will I replace it? nah.... that thing gets so beat up going through airports, it's probably similar to what I gave it doing somersaults down the slope that day.

oh, i'm in the market for a new board....but they cost too much here!

Motorcycle helmet damage.... I've dropped a couple helmets over the last couple years. More like they fell off the seat or wind blew them off, etc. Falling from that height I'm not too worried about. But if I came off and hit my head, I'd probably look to get rid of that lid.

Whether it is paranoia about safety or my vain fear of looking dorky with a scraped helmet is a different question.... :violin:
 

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Tokyo i had a similar accident on a snowboard........
Three consecutive days of snowboarding, last day......15' launch, 25' table top mixed with a 180 and a heel edge caught on the landing makes for a pretty bad concussion....knocked me out cold for who knows how long.......i woke up to two young kids asking me if i was ok.

i made to the bottom of the hill seeing a kaleidoscope out of one eye.
8 hours later i couldnt remember where i skied that day, when i got back to the hotel i couldnt remember what room i was in and i barely remembered the 45min ride to denver from brekenridge.
It all came back to me the next morning.
This was with a helmet on!!!!! i can only imagine what would have happened without one.......that was the day i became a true believer of helmet usage.

As for replacing a "dropped" helmet.........C'mon people the outer shell absorbs ALL of that impact........thats like dropping your cell phone.
Now after an accident there is no question!!!!.....it MUST be replaced.
Just my opinion
Chris
 
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