Heat dissipation question- Mtbr.com
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  1. #1
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    Heat dissipation question

    I've seen several comments on heat dissipation and how important it is. I'm wondering how a light like the Lupine Betty deals with it, since appears to have insufficient surface area compared to the amount of light produced. Can anyone give feedback on that and how it would affect this type of light.

    Thank you.

  2. #2
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    Lupines will throttle down current when they get too hot.
    Surface area...... That is one of those voodoo areas of building. I think as long as you are rolling at a fun pace most lights will have ample cooling.

  3. #3
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    Quote Originally Posted by odtexas
    ....Surface area...... That is one of those voodoo areas of building. I think as long as you are rolling at a fun pace most lights will have ample cooling.
    Agreed. A bit of voodoo.

    Assuming you have a good low resistance thermal path to the housing from the LED, and a Lupine does, then air speed and temperature are the big factors in the unit heating up or not.

    Running a 10 Watt light in the day (daylight running light and the light body is black, so soaks up solar) temperatures in the mid to upper 90 F (34 C +) at a moderate uphill speed and it got a bit warm to touch but did not trigger the 50C power down programmed in. Stopping to give directions made it hot but also did not trigger it. On the downhills it cooled to pleasantly warm. At night, at high 70's to mid 80's (25-29 C), it is just pleasantly warm riding slow and cooler on downhills. In winter, riding below the freezing point, it feels as cold as the bike frame day or night and speed was irrelevant. The ceiling fan was enough to keep it at body temp with the air at room temp. (72 F/ 22 C or about that). I imagine if I rode in higher temps (100 F +) and didn't keep the pace up, it would throttle back and be painful to touch.

    YMMV.

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