Modding a Planet Bike 5000x, driver suggestions please

[mrbubbles]

I got one of these

It's a Planet Bike 5000x powered by a 3.5w halogen with the runtime of 30hrs on low, and 20hrs on high.


What kind of boost driver can I use for this light for powering two P4 SSC?

Currently, the switch and the circuitry inside is voltage regulated, I measured it at high voltage output is 6V, while low voltage is 5V.

4.8V 4AA powered seems sort of ideal for a powering two P4 SSC with a boost driver.

My other question is, can I use the circuitry to change light output of LEDs? (I'm guessing not, I haven't measured the current draw from High or Low)

Is there a boost driver in the size of a Micropuck that I can put between the board and the led to power 2 P4 SSC?

If all else fails, I'll just get take out the board inside the Light and dump in a Fatman with pot and switch.

I sought out to modify a light like this because I like the compactness without an extra dangling battery pack to strap to the stem and it is easy to take off.

Any suggestions will be greatly appreciated.

 

[alexlockhart]

I don't have much in the way of a specific driver recommendation, but I do know that you'll be best off running whatever driver you decide on straight from the batteries - you'll want to take out all the electronics that are in there now.

Also, you should think about the runtimes. 4AA NiMHs have about 12WH total, and 4AA alkalines have about 15WH total, so if it really does have 30 hours runtime on high and 20 on low (did you measure it or are those the claimed specs?), that means it's only drawing 0.5W from the batteries on low and 0.75W on high. A 3.5W load will drain 4AA batteries in about 4 hours, and that's fully dead, not half-brightness. If you can measure the amperage draw of your light, you'll know what it's really doing.

An SSC P4 (U-bin) can draw 3.7W (3.7V at 1000mA) and will output over 200lm at that level. Your current halogen, at around 20-30lm/W, is only putting out 30lm at best if it's running for 20 hours on 4AA, and about 100lm if it's drawing the 3.5W you state, but as I said before, that would drain your batteries in about 4 hours. Running the SSC P4 at 1000mA will provide the same 4hr runtime, but with at least double the brightness. If your light really does run for 20 hours on high, it's only producing 30lm, and if you want 15 hours of runtime with the SSC P4, you should run it at 350mA, which will draw about 1W. That'll produce about 100lm, which will be at least 3x brighter than what you currently have at the same runtime. Since your batteries can't run even 1 SSC P4 at its maximum for more than 4 hours, you don't need 2 of them.

You should also consider how the beam will be shaped - will you be using the stock reflector or replacing it with a reflector or optic designed for the SSC P4? You'll get much better beam pattern results from something designed for the LED. You'll be hard-pressed to fit 2 LEDs in that small housing with any kind of reflector or optic - they make optics for arrays of 3 LEDs which might fit in your housing, but again, your batteries limit your power to less than what 1 LED can do, so you're probably best just using one.

You may not want to spend the money, but if you're looking for a good, very bright LED light in a small, self-contained package, the L&M Vega is probably your best bet. There are also a number of cheap flashlights on DX or KD that would work great with a Twofish mounting block, but the best of those use CR123A or 18650 Li-Ion cells, for which you'd need a separate charger.

Alex