modifying a motorcycle tail light...

[RedBaronX]

OK... there are two nodes on the bottom of the bulb. There are two wires that connect to each of those nodes... When I touch either of those wires to the positive connection of the battery I have-- nothing happens. When I complete the circuit by touching a wire to the side of the bulb and back to the negative connection of the battery, the light comes on-- BRIGHT. NO matter which of the two nodes on the bulb I touch it comes on at the same intensity. Maybe that isn't how it's "supposed" to work, but that is what I have.

That is why I am modifying what I have by adding a second set of LEDs that will be running on their own circuit.

And I already have a brake handle with a brake light switch. Bought it about a year ago. But that's a useful link if for some reason the switch I have fails (it IS used.)

 

[IbedaYank]

side of the bulb is negative
one lump will be running lights the other will be brake/turn
best way to tell would be to use jumper wires one will out shine the other thats the brake light side
if give me a about half hour i can tell ya witch is witch on a standard bulb
there is 2 little metal studs on the side of the bulbs that are at differnt heights

 

[IbedaYank]

ok...looking at the bulb with the shorter of the studs that hold the bulb facing you the brake light element is the one to the left

 

[RedBaronX]

ok...looking at the bulb with the shorter of the studs that hold the bulb facing you the brake light element is the one to the left

one stud isn't SHORTER, but one is definitely closer to the bottom of the bulb...

and in my not-terribly-scientific test (turn on the bathroom light, connect one configuration to the battery, shut off light; repeat with other configuration) they look like the same brightness... (the bulb is 20 something individual LED lamps, and they all come on at the same time with both connections)

 

[IbedaYank]

one stud isn't SHORTER, but one is definitely closer to the bottom of the bulb...

and in my not-terribly-scientific test (turn on the bathroom light, connect one configuration to the battery, shut off light; repeat with other configuration) they look like the same brightness... (the bulb is 20 something individual LED lamps, and they all come on at the same time with both connections)

yeah thats what i mean by shorter
what did you use to test the light?
regulated power supply or FULLY charged battery?
remember a led is a light emmiting diode

 

[RedBaronX]

like I said, I'm going with what I have and what I know... battery + wires + lamps = tail light. I don't have a regulating power supply...

 

[IbedaYank]

this is what i do for work...boss hates wiring bikes as in motorcycles mostly pre 1975 british

regulated power supply is just something like a battery charger but puts out 13.8 volts dc and plugs in the wall..... very usefull for testing 12 stuff without the need for a battery on your bench
its all switches bits of wire and bulbs just used in the right order and places