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  1. #1
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    Help powerin getting led light from battery

    I have a led tail light for a motorcycle. The manufacturer says it's .3 watts. They say I need a regulator. Is that true? How do I power it most easily?
    Thanks for the help

  2. #2
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    To few data to tell you anything for shure. Do you have any pictures? If there is single led die then it is vey likely you need step-down DC-DC converter to get lower input voltage or some current limiting circuit. 0.3W doesn't tell what is the input voltage or max. current.

  3. #3
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    The manufacturer just told me the light takes 2 watt total to run. Does this help?

  4. #4
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    My plan was to power the led light ( I think there are 6 .3 watts lights for a total of about 2 watts) with a 2900 mah glow worm battery. Can I go directly to the light from the battery or do I need a regulator and if so what size?
    Thanks for any help.

  5. #5
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    Can't help without more info about the light. Post a link to the product web page so we can see the specs.
    GoPro adapters for bike lights http://www.pacifier.com/~kevinb/index.html

  6. #6
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    Stealman,

    I'm not going to help you with this anymore because it is apparent you have zero interest in even trying to be compliant with regulations regarding the use of motorcycles on the street. 2W is a marker light and doesn't come close to having enough output for a tail lamp, let alone a brake lamp. Get a 20-30W lamp, then we can talk. The lamp you have is for decoration, or as a side marker for a trailer.
    I will suffer no butt-hurt fools!

  7. #7
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    https://www.rockymountainatvmc.com/p...LED-Tail-Light

    Here is the link it is a legitimate tail light. I just don't know anything about low voltage electronics and am trying to learn a little something. It looks like there are a lot of people on this forum that know at least enough to properly power this light.

  8. #8
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    Says nothing about voltage. So what is default voltage on motocycle? Very likely it's designed for direct connect to bike power system.

  9. #9
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    Since your thread on the bike light forum related to converting a dirt bike to street legal, I'm going to assume that is the case here too....

    Your dirt bike probably just has a single pole alternator coil often referred to as a Stator. The voltage and frequency it develops will be directly related to the engine speed. Unless already equipped, you will need a voltage regulator. You may also need some kind of storage device (Super Cap or Battery) for this tail light to work because the stator may not generate enough power at idle or low engine speed to keep the light on. Additionally you will need switches on the brake pedal and brake lever to activate the brake light portion of the tail light.

    Honestly, I think searching some forums directed toward off-road motorcycles might provide more helpful information on how to make this work for you.
    GoPro adapters for bike lights http://www.pacifier.com/~kevinb/index.html

  10. #10
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    Thanks for the help. I am not going to connect to the motorcycle electrical system at all. I think the motorcycle is making it more confusing. I am connecting the light to a rechargable battery. I guess I just need to know how to match the electrical requirements for the light from the battery. I don't know how to do it though. Where can I learn about how this stuff works?

  11. #11
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    If I assume bike has 12V and battery from 3-4.2V you need Boost converter like this https://www.ebay.com/itm/DC-DC-Boost...e/112468350952
    You adjust output voltage to 12V or whatever original voltage is and you are done. Use digital multimeter to check output voltage before you connect anything so it won't be to high at start.

  12. #12
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    I am not connecting it to the motorcycle. For get about that part. I want to run the light from a 2900 mah gloworm battery.

  13. #13
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    Amazon says it's 12V. You can't run it from a Li-ion pack without a converter. You should have bought a $20 12V Sealed Led Acid battery and charger like I suggested. This is not street legal, don't ride on the street.

    I'm still not helping you, because you're going to do this and ride on the street anyway and get a ticket or get killed because of no brake indicator and from the Amazon reviews it's a pretty pathetic light.
    I will suffer no butt-hurt fools!

  14. #14
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    Quote Originally Posted by stealman View Post
    I am not connecting it to the motorcycle. For get about that part. I want to run the light from a 2900 mah gloworm battery.
    Jeez dude, Ledoman was trying to tell what to do to run it from the Gloworm battery. Did you not get that?

    Lets try to make this really simple...

    The light is for a motorcycle. Motorcycle electrical system is ~12V, so light must need 12V. Got it?
    Gloworm battery will be 3.7V or 7.4V depending on model. That's less than 12V. OK?
    Since the battery is less than 12V, you need a device to boost the battery voltage to give 12V to the light. The device that Ledoman linked does that.
    Once you get the voltage converter device you will need to wire it all up. You'll need to wire switches to your brake lever and pedal to make the brakelight feature work too.

    I'll be surprised if you can do it.
    GoPro adapters for bike lights http://www.pacifier.com/~kevinb/index.html

  15. #15
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    I get that he was trying to help , but I didnt understand. You spelled it out for me in a way that I understand. Thanks for the info guys.
    Last edited by stealman; 02-23-2018 at 08:16 PM. Reason: messed uo

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