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Thread: My Helmet vs Gravity

  1. #1
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    My Helmet vs Gravity

    The bitch Newton claimed to be called gravity decided to play a joke on me the other day, it resulted in my helmet falling from a height of about 500cm onto concrete and rolling into dirt.

    Just wondering if I should be worried about the condition of the helmet? There are no noticeable defects, not even a scratch. But Im still worrying that it could be damaged internally or something.

    Could someone please advise whether this height drop needs to be looked at?

  2. #2
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    5 metres is quite a drop. Although there may not be external damage there may well be damage to the internal structure designed to absorb the impact.

  3. #3
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    500cm I would definitely be concerned... you may mean 500mm (ie half a metre)?

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    If it's a drop of 500mm you are unlikely to have damaged it. The helmet is designed to absorb the weight of your head in an impact. Unladen helmet is rarely damaged by a simple drop.

    Don't believe it? Check this out...

    http://www.jaylenosgarage.com/video/...elmets/283819/

    From about 7.15 onwards he discusses dropping a helmet.
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  5. #5
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    Quote Originally Posted by slofox View Post
    If it's a drop of 500mm you are unlikely to have damaged it. The helmet is designed to absorb the weight of your head in an impact. Unladen helmet is rarely damaged by a simple drop.

    Don't believe it? Check this out...

    http://www.jaylenosgarage.com/video/...elmets/283819/

    From about 7.15 onwards he discusses dropping a helmet.
    Interesting post.
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  6. #6
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    Quote Originally Posted by numbersixteen16 View Post
    The bitch Newton claimed to be called gravity decided to play a joke on me the other day, it resulted in my helmet falling from a height of about 500cm onto concrete and rolling into dirt.

    Just wondering if I should be worried about the condition of the helmet? There are no noticeable defects, not even a scratch. But Im still worrying that it could be damaged internally or something.

    Could someone please advise whether this height drop needs to be looked at?
    Was it off a second storey roof?

  7. #7
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    Yes 500mm, my mistake

  8. #8
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    The internals of most helmets are polystyrene.
    The forces involved in permanently pressing polystyrene and permanently deform it without cracking it are quite complex and difficult replicate in a 'fall' type situation.
    Contrary to popular belief helmets are not 'one-shot-wonders'. If the elements of the helmet do not permanent deform (aka everything bounces back) the structural rigidity is actually very close to original spec.

    Long story short - if it didn't crack, and the polystyrene didn't compress it is fine.
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  9. #9
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    Quote Originally Posted by avgas View Post
    The internals of most helmets are polystyrene.
    The forces involved in permanently pressing polystyrene and permanently deform it without cracking it are quite complex and difficult replicate in a 'fall' type situation.
    Contrary to popular belief helmets are not 'one-shot-wonders'. If the elements of the helmet do not permanent deform (aka everything bounces back) the structural rigidity is actually very close to original spec.

    Long story short - if it didn't crack, and the polystyrene didn't compress it is fine.
    the only problem is checking the polystyrene didn't compress But from 500mm it is unlikely to have, all the force will have probably been taken by the shell and if that hasn't cracked then you are not likely to have any problems. Also with the helmet not having a head in it the head will more readily flex on impact with nothing to compress the polystyrene and the shell will therefore be damaged first if anything.

  10. #10
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    Try checking with the manufacturer to see what they say about it.

  11. #11
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    Quote Originally Posted by avgas View Post
    Long story short - if it didn't crack, and the polystyrene didn't compress it is fine.
    ^ This

  12. #12
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    Quote Originally Posted by oneofsix View Post
    the only problem is checking the polystyrene didn't compress
    Its actually quite easily, Put it on your head and try and move the shell.
    Then take it off your head and try the same thing.
    If the shell shifts at all the poly has compressed/deformed.
    Works about 70% of the time.
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