I have been trying to figure out the best way to make my own LED tail lights for my motorcycle. I have already made the board and have the LED's wired in. I just can't get the running light and brake lights to be what I consider bright enough. I got one of those 100 packs of LED's off ebay but am only using 72 of them. They are 20k mcd and have a Vf of 3.2 to 3.8. They are rated at a peak forward current of 75 mA and a max continuous current of 30 mA. I am running these in parallel and have a single ground wire and a running light power wire and a brake light power wire. I have tried hooking up a 33 ohm resistor and its pretty bright through the lense but the resistor gets hot quick and I cant imagine that the LEDs would last very long with that much power going through them. I have noticed that the LED's are much brighter when the light isnt filtered through the lense. But I am hoping I can make them bright enough that it wont matter that the lense is there. I have seen the LED lights on cadilacs and I want mine to look like that. Maybe wishfull thinking but I guess we'll find out.