Cheap DIY Tail light that runs off the computer


Hi everyone. Thought I'd share my wired-in Radmini tail light. Should also work with other bikes in the family. This one dawned on me as I surveyed the materials I had on hand, and cost me nothing, but from scratch could come in under 10 bucks.

I have a roll of cheap 12v red led strip lights, which are waterproof and run in parallel, so you can cut them in sets of three to 300 LED's depending on your needs. I suddenly realized I could wire 4 pieces in series, so they would run on 48V. Four strips of six LED's fit nicely onto a piece of my ubiquitous coroplastcut to fit on just the base of the stock LED light. Some magical zip ties, silicone glue for waterproofing, and optional connectors, and we were in business! 24 LED's should equal about two watts. The strips are white so it doesn't look beautiful, but they should work well. I used an old broken 6' USB cable to match the bike's cabling, and ran it all the way to the front light, instead of tapping in, just to avoid cutting into the wire bundle. I scraped off some insulation right where the front light plugs in, soldered the cable on, and applied new shrink tubing.

Costing nothing it was a no-brainer, but even at around 10 bucks it's a lot cheaper than other 48v options.

Light strip: (wow, $4.74 these days?)

EDIT: If anyone decides to do this, you can find the red LED strips with a black background on amazon. Would look much nicer when turned off... Unless you have a white bike!

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