16.8V 20W bike light?

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Flintrock
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16.8V 20W bike light?

I've got a couple 8 cell 4s 16.8V battery packs already.  Basically I'm looking for something a bunch like this:

https://www.fasttech.com/products/0/10009797/5016100-3-led-4-mode-3600lm-led-bicycle-light-headlamp-set

(It's a 4 led helmet/handlebar mount light housing, with separated battery back that runs from 16.8 V)

 

But not necessarily with the batteries included, preferably with a bit more power, aiming more for 20W, but not much more, preferably real CREE LED's of course.  Some modding could be ok (including changing the LED' so long as they are separated from the driver board, or adding some 7135's if really needed, etc.).

 

Not many things exist already in 16.8V.  Most options would probably thus require a complete driver change I guess. Something like a solarforce x3 looks nice, but it seems that requires driver changes and sometimes serious tool work for cooling mods (I don't want to do that).

 

I bike quite fast in dark places with dark clad foot traffic, so need a good spot to look down the trail, but still want some wide spill.  The beam shot of that FT model looks maybe floody.

 

Low frequency PWM means useless to me, but low power modes are not a must-have anyway.

I'm hoping to spend under $50. 

 

Any good suggestions?

 

UPDATE: I'm updating the question with the idea that I will just run 3 or 4 LED's in series off a one-mode buck regulator, so all I need is a good housing (preferably with good led's included) that fits the bill for beam pattern and 20W power handling. A tiltable (while riding) mount is also great (for being courteous at times), but usually I can rig something for that.

Edited by: Flintrock on 09/13/2016 - 23:54
kwarwick
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You’re not going to find anything in the cheap Chinese bike light category like that… they are pretty much exclusively 7.2V/8.4V and some really cheap ones are 3.7/4.2V. 14.4/16.8V batteries are pretty much used only by higher end and DIY lights.

You’re correct that most would require a complete driver replacement, assuming you could find something that would fit… something like http://taskled.com/ drivers would be my recommendation, but you’re going to blow that $50 budget on the driver alone!

SawMaster
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High output isn’t dependent on high voltage so perhaps a re-think of your approach can get you what you want within budget. Requiring the use of any given component can have a very adverse effect on the whole if it is not close to optimum for the goal you’re striving for.

Phil

Flintrock
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No it doesn't, but I have other uses for the high voltage, and yes I'm considering other routes.  Anyway, I'm thinking about just wiring 4 x xm-l2 in series with a dumb regulator, either voltage or current, in front of them.  A power switch isn't a problem.  Not everything needs a micro-controller to turn it on.  I just want to get oh 1.3 amps of current to go through some diodes. I'd just need a good suggestion for a host and to hope I can find a suitable regulator that fits in the space.

Flintrock
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Like tell me this isn't cute:

https://www.fasttech.com/products/0/10003417/1253701-mini-dc-dc-converter-voltage-stabilizer-regulator

Variable input/output buck regulator (the real kind) rated for 3A.  

 

If I ever wanted to I could replace the pot with an external one. 

 

I had first seen this linear regulator:

http://www.st.com/content/ccc/resource/technical/document/datasheet/16/8e/9b/71/8e/42/45/65/CD00156614.pdf/files/CD00156614.pdf/jcr:content/translations/en.CD00156614.pdf

 

which I figure could be "rigged" up with some duct tape so to speak, but the buck regulator is easier (already rigged up, including pot control) and probably more efficient too and it still leaves me $47.46 left for a host and leds.  

  

So, back to suggestions for a head-only host?  3 or 4 led? can handle 20W of heat?  Good throw and decent spill. Nobody?

 

 

wle
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why not just get 2 of the cheapish current lights, like thorfire bl-30?
wle

"You never have the wind with you - it's either against you, or you're having a good day."
    Daniel Behrman, "The Man Who Loved Bicycles".
It never gets easy, you just go faster.   
-Greg Lemond.
       ,ø¤º°`°º¤ø¸,ø¤º°`°º¤ø¸,ø¤º°`°º¤ø¸

Flintrock
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Actually I see now there are so many neat little simultaneously and adjustably voltage-and-current-limited/regulated buck converters all assembled and ready to use on Amazon these days.  Most are 26mm by 60mm, (by 10mm or so) and it's hard to find a space like that in most lights, but so what, I can run it from inside my battery bottle, or elsewhere if that's too hot.  It's still pretty tiny.  They run around $10, but probably smarter and more safely adjustable than going with a cheaper straight voltage regulator.  

 

With a pot control for current, who cares about losing the clicky controller? (Blinkies have no place in my life)  Just mount a remote pot somewhere.  I like that's it's analog control. 

 

So yeah, I just need a good light.

Flintrock
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wle wrote:
why not just get 2 of the cheapish current lights, like thorfire bl-30? wle

Not a terrible idea.  Best answer is because it's twice as hard to remove and to aim as buying one and takes up more space on my handlebars. 

wle
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oh
ok
i’m pretty happy with any of the cheap LED lights though
after having suffered through years of expensive unreliable nicads and dim incandescent bulbs!

wle

"You never have the wind with you - it's either against you, or you're having a good day."
    Daniel Behrman, "The Man Who Loved Bicycles".
It never gets easy, you just go faster.   
-Greg Lemond.
       ,ø¤º°`°º¤ø¸,ø¤º°`°º¤ø¸,ø¤º°`°º¤ø¸

Flintrock
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Does anyone know where or if one can find a GOOD solarstorm x3?  with a good cooling?  It seems there is some variation in sources or lights having this name on them.

 

Incandescent isn't dim, you just didn't use enough juice, but it's hard to get there with NiMH.  

 

Supposedly there's a new tunsgten halogen in the works.  I hope it works out.  It would be great if LED's could end up as part of history.  I mean if we had bulbs that didn't care about cooling and just gave nice glows again, but as much light as LED's.