You're missing the point entirely.  The EPS liner is not subject to significant impact forces when there is no headform present.  However, the SHELL of the helmet is.

The composite is designed to absorb impact energy though controlled destruction of the resin matrix.  It is entirely possible for the laminate to have sustained severe damage without being visable to the naked eye.  The damage likely to occur is called delamination.  Delamination is the failure of the bond between layers of composite reinforcement.  This bond failure means that interlaminar shear forces cannot be transmitted from one lamination to another.  The result is a severe reduction in bending strength and therefore impact resistance.  Due to the flexible nature of composites, it is possible for the laminate to be subjected to a force great enough to cause delamination but still allow the structure to spring back to its "as built" shape.  The only way to determine the extent of the damage only through the use of non-destructive testing methods such as ultrasound.

"Faith" has no business in the safety business or anywhere outside of a church.  Webster's defines faith as "belief which is not based on proof."  I don't tell the pilot of an airplane with 300 people aboard that I have faith in airplane to make the journey over the Atlantic.  I tell him that I know the airplane to be safe and prepared to make the trip without question.  I don't suggest you have faith in your helmet, I suggest you know for a fact that it is safe and capable of protecting your brain in a crash.

Spending the rest of your life getting steak dinners through a tube isn't worth $200.  Buy a new one, or have your current lid tested by the manufacturer.

It's probably fine. I dropped my helmet from over 4 feet once, and sent it off to Shoei to be sure. They said that, despite the exterior paint being chipped off, the helmet was perfectly fine.

Dirt riders have their helmets go through a heck of a lot more than we do, and they don't replace their helmets after every drop.

Quote from: GeeP on February 19, 2007, 04:03:08 PM
You're missing the point entirely.  The EPS liner is not subject to significant impact forces when there is no headform present.  However, the SHELL of the helmet is.

The composite is designed to absorb impact energy though controlled destruction of the resin matrix.  It is entirely possible for the laminate to have sustained severe damage without being visable to the naked eye.  The damage likely to occur is called delamination.  Delamination is the failure of the bond between layers of composite reinforcement.  This bond failure means that interlaminar shear forces cannot be transmitted from one lamination to another.  The result is a severe reduction in bending strength and therefore impact resistance.  Due to the flexible nature of composites, it is possible for the laminate to be subjected to a force great enough to cause delamination but still allow the structure to spring back to its "as built" shape.  The only way to determine the extent of the damage only through the use of non-destructive testing methods such as ultrasound.

"Faith" has no business in the safety business or anywhere outside of a church.  Webster's defines faith as "belief which is not based on proof."  I don't tell the pilot of an airplane with 300 people aboard that I have faith in airplane to make the journey over the Atlantic.  I tell him that I know the airplane to be safe and prepared to make the trip without question.  I don't suggest you have faith in your helmet, I suggest you know for a fact that it is safe and capable of protecting your brain in a crash.

Spending the rest of your life getting steak dinners through a tube isn't worth $200.  Buy a new one, or have your current lid tested by the manufacturer.

I could say confedence.  its a personal choice dont knock anyone either way. remember some states dont even have helmet laws. now would I or would I not wear a helmet. im sure once or twice I would ablige my want not to.  can't go through your whole life wondering what if. if your going to go or end up some way its going to happen no matter how many helmet you buy.

I've already met a car's windshield with my face one time.  It was a tie though, I broke it and I it broke my jaw.  And it wasn't steak through a straw it was anything I ate/drank, everything came through a straw for three months while my jaw was wired shut.  Bicycle, the pedal kind, vs elderly driver and there tank of a cage... good times.   So I'm not down playing the importance of proper gear.  When I ride I have almost full gear, just lack "motorcycle" boots, instead I just wear steel toed ones.  And that is why I'm on here asking for your opinions, but don't get mad if I don't immediately buy one regardless of what anyone says, even if the shoei people test it and say its bad, b/c as stated initially, I can't afford one right now.  And no one will deny that any helmet, even a possibly damaged one, is better than no helmet at all, because that would be my only other option.

Quote from: NiceGuysFinishLast on February 19, 2007, 01:16:44 PM
...you can ship it back to them and have it checked out...

Do you know who to contact about this?

Just call the 800 number that came with your helmet, I believe.

Quote from: NiceGuysFinishLast on February 18, 2007, 10:17:42 PM
You've never read any of the articles that have been posted here/various places on the internet, have you? Every one I've ever read (including independent evaluations, not just sponsored articles) has endorsed replacing the helmet even if it was dropped empty.

Actually, I have read a lot and posted in some (but thanks for asking ).  I'm simply saying there's a HUGE difference in dropping an empty helmet and the same speed of impact with a head inside it. 

I do understand that delamination may not be visible on the outside, although there would almost have to be some deformation or evidence of such.  I'm personally not buying that a helmet cannot withstand a drop from the height of the bike seat without damage to the shell.  If a helmet could delaminate from such a drop, it would offer VERY little protection in a real world crash.

OTOH, if I had even a minor accident that scuffed my helmet, I'd replace it.  I am MUCH more worried about the liner compressing than the shell delaminating from a minor hit.  As I have posted before, I'm 49 and I own a Z1R precisely because it will protect my shock-sensitive middle-aged brain better than a Snell rated helmet.  I'm not surviving a hit like the Snell test anyway!  Younger brains might...

Hah, I doubt my younger brain will survive any better than your addled.... err... older brain would..

Assumptions:
Mass of helmet: 1kg (works out to 2.2 lbs, the weight of a Shoei)
Mass of head: 5kg
Height: 1.25m (~4 ft)

Energy = m*g*h = (1kg)*(9.81 m/sec²)*(1.25m) = 12.2625 joules

Snell helmets are tested with repeated impacts of 250 joules (IIRC), with a maximum of 300 joules.

With a head in the helmet, the energy is multiplied 6 fold:

E = (m_helmet + m_head)*g*h = (1kg + 5kg)*(9.81 m/sec²)*(1.25m) = 73.575 joules

Significant differences between those two numbers.

Personally, I think it is fine, but send it to the manufacturer to have it checked out just to make sure.

Quote from: ixolas on February 19, 2007, 10:46:57 PMWhen I ride I have almost full gear, just lack "motorcycle" boots, instead I just wear steel toed ones.  And that is why I'm on here asking for your opinions, but don't get mad if I don't immediately buy one regardless of what anyone says, even if the shoei people test it and say its bad, b/c as stated initially, I can't afford one right now.  And no one will deny that any helmet, even a possibly damaged one, is better than no helmet at all, because that would be my only other option.

You're on the right track.   

Quote from: ixolas on February 19, 2007, 10:46:57 PM
When I ride I have almost full gear, just lack "motorcycle" boots, instead I just wear steel toed ones.  And that is why I'm on here asking for your opinions, but don't get mad if I don't immediately buy one regardless of what anyone says, even if the shoei people test it and say its bad, b/c as stated initially, I can't afford one right now. 

You'd be surprised how much you can get a decent helmet these days. I got a Fox MX helmet (DOT and Snell approved) for $60 shipped off eBay, brand new. Discontinued graphic in my size

fell out of your hands onto carpet?  i highly doubt there's anything wrong with it.  it probably takes a bigger beating at the store moving from shelf to shelf.

Or in shipping...


Think about it...  If you dropped your head 3ft onto carpet, you probably wouldn't even have a headache...   



But...  You can use it as an excuse to get a new helmet.  That's my plan...  When I want a new one I'll just drop it and tell my wife it's broken.