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  1. #1
    Senior Member datlas's Avatar
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    Ultrafire problem/help!

    I don't know if this problem is idiosyncratic, but maybe the collective wisdom of the forum can help:

    I have a DX Ultrafire light on my bike, and it only has (officially) two settings: on and off.

    But when it is on, it seems to alternate between on (high) and DIM...and the DIM is quite dim, I would estimate less than half as bright as the normal/high setting.

    It seems to randomly jump between high and dim...not related to when I turn it on/off....not related to whether I am using fresh or older batteries, and it happens with both disposable AAs and rechargables.

    I am not pleased with this situation as the light seems to spend most of its time "dim" and its usefulness when dim is really marginal.

    Anyone else experience this problem, or any suggestions?

    Doug

  2. #2
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    have you cleaned the contacts, etc? I have also read that some springs will contact with a sharp point and filing this point down can solve some problems.

  3. #3
    Senior Member mechBgon's Avatar
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    Quote Originally Posted by datlas View Post
    I don't know if this problem is idiosyncratic, but maybe the collective wisdom of the forum can help:

    I have a DX Ultrafire light on my bike, and it only has (officially) two settings: on and off.

    But when it is on, it seems to alternate between on (high) and DIM...and the DIM is quite dim, I would estimate less than half as bright as the normal/high setting.

    It seems to randomly jump between high and dim...not related to when I turn it on/off....not related to whether I am using fresh or older batteries, and it happens with both disposable AAs and rechargables.

    I am not pleased with this situation as the light seems to spend most of its time "dim" and its usefulness when dim is really marginal.

    Anyone else experience this problem, or any suggestions?

    Doug
    On some lights, momentarily switching them OFF is how you cycle them between their different output levels. So if your batteries are momentarily losing contact from the vibration of bike use, the light could be all "oh, he momentarily cut power, then resumed it... that's my signal to SWITCH MODES!"

    As a quick solution, see if you can put your batteries inside one wrap of paper and slip them into the battery tube with the paper around them, so there's less room for them to slap around and possibly lose contact.

  4. #4
    Senior Member Ziemas's Avatar
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    Sounds like a bad contact somewhere. I had a DX light that did that; I solved the problem by making sure it was screwed together quite tight and the contacts were clean. In my case it was the contact in the head of the light that was loose, not the tail.

  5. #5
    Senior Member datlas's Avatar
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    Thanks for the tips I will give them a try!

  6. #6
    Galveston County Texas 10 Wheels's Avatar
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    Quote Originally Posted by datlas View Post
    Thanks for the tips I will give them a try!
    I found that putting masking tape on batteries will stop any movement inside the flash light.
    I also write the date on the masking tape. You will then know how old and how long the battery will last.
    [SIZE=1][B]What I like about Texas[/B]
    http://www.youtube.com/watch?v=PGukLuXzH1E

    Set F1re To The Ra1n ( NY Night Rain Ride)
    http://www.youtube.com/watch?v=W7jfcWEkSrI

  7. #7
    BeaverTerror Yan's Avatar
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    Try unscrewing the tailcap slightly.
    Yan

    2013 True North custom touring; 2010 Novara Randonee; 2009 Unicycle.com Club 24"; 1989 Miele Tivoli; 1979 Colnago Sport

  8. #8
    Senior Member datlas's Avatar
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    Update:

    I took the light apart, cleaned and buffed up the contacts....also wrapped the batteries (I used a post-it note, white collar crime alert!).

    The good news: Now instead of being dim 80% of the time, and bright 20% of the time, the ratios have reversed, and it is bright 80% of the time.

    The bad news: it is still dim, randomly, at times.

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