Super simple DIY remote headlights

In my search for an easy highbeam headlight option from this thread I tried a few different variants of cheap led flashlights. Mounting them to the trucks with rubber “c” clamps was easy and secure. However, all of them eventually began to fail. Usually a flicker in which the battery was likely loosing contact.

I decided that I wanted to make something more reliable and permanent. This led me to ebay bike lights:


I tested this model in particular for a while with it simply taped to the board. It held up to the vibrations well and was brighter than anything else I tested. The entire body is metal as well as the internals. At under $20 USD it seemed like a good purchase.

I could have just 3D printed a mount and battery case for the underside of the board and finished there, but I wanted this light to be remote controlled so I decided to experiment.

This model runs off a 2s2p battery pack of 18650 cells. So the voltage range is somewhere between 6.8-8.4 volts. I happened to see a cheap remote relay switch on Amazon that operated at this voltage so I thought I’d give that a try. image

Easily enough it works. I wanted this to be simple and reliable so I didn’t keep the lights original PCB. Instead I opted to use a couple of resistors with a switch for brightness control. Not too experienced with circuits, but I’ve managed in the past through experimentation and this couldn’t get much simpler.

This is the basic wiring diagram, except I used a switch and two resistors before the leds for high and low beam. image Looking up the data sheet for the LED’s used in my light it seems that they consume a bit more current than I assumed:

(XM-L T6 )

I went through my scrap parts bin and found a couple of hefty resistors (10ohm and 2.7ohm) that I figured wouldn’t get to hot. After testing them for a while they don’t, but I’m still a little concerned about power dissipation.

Anyway now that it’s tested I’ll print an enclosure for everything and mount the light. The remote should be pretty easy to take integrate into my boards remote.

Thanks for reading. Comments, ideas, or suggestions are welcomed.


I was looking at buying a couple of these for my next build, thanks for confirming their brightness. Right now I’m doing what you did, I have a small separate battery pack for the lights, but it would be nice if I could just draw from the main pack. Are you planning on trying that?

The bike light I purchased came with that battery pack. I’m basically drawing directly from the battery pack with a resistor before the led.

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Made a quick test run and it works great. I really like the ability to turn the lights off via remote. It also came in handy to signal people. Unfortunately as I expected there is passive drain on the battery so it dies if I leave it plugged in.

Anyone know how I could improve this? I feel this could be a really easy project for most and be comparable to something like shredlights except remote controlled.

image image

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