I really liked this Instructable:
We put that all together in one afternoon for 2 bikes, with blue LEDs. We idiots didn’t consider that blue lights are forbidden on bicycles too, so now we have to redo it with orange lights if we want to use our bikes on the streets. And at the moment the weather is still to bad and the mood not there to do it again. What a pity, it really is improving your visibility on the street at night.
Per wheel you need:
- 1 9V battery block
- bright LEDs (>10000mcd)
- some wires
- heat shrink tubes if you want to increase the lifetime
- zip ties
The amount of LEDs is defined by the voltage they need, their brightness and your spokes. We had blue LEDs with forward voltage of ~3.5V so we took 6 per wheel: 3 in series makes 9V and two of them parallel.
Mounting was a bit tricky. First we soldered some wire tails to the LEDs. Hint: making a knot into the cathode tail makes it easier later to find the right ends. Then we took different kinds of heat shrink tubes to protect them from water and corrosion. We mounted them ~4 centimeters away from the rims to ensure that the LEDs have enough distance to enlighten a bigger area. Using 2 zip ties per LED and wrapping the tail around one spoke kept them in place.
We tried to keep all the wires as tight as possible and every connection got a heat shrink tube. The 9V Block is kept in place with a zip tie and the battery connector, that is wrapped tight to one spoke very close to the center.
All in all its a fast, cheap, safe and shiny hack for your bicycle. Lets hope someone would not steal it because of this little feature. 😉
Pictures of the hack in action are on the way!