quentin99 wrote on 05/16/14 at 13:01:08: Im looking at the wiring diagram and the side stand relay is what the brake light switch wires into. And from there it wires to the horn which works, the neutral indicator which dosent work and the turn signals. Which in my opinion blink a little slow.
The bulb in the tail light which i believe to be an original to the bike. Looks like it is a 3 filament bulb? It is set up like a 2 filament bulb but one of them has a post in the middle of it. I tried replacing it with the dual filament bulb that the blinkers use and that did not fix the problem.
The black wire with the white dashes that is common to the horn, turn signals, side stand switch, etc.....is the common ground wire. If you follow that black/white wire long enough in the circuit....you will see that it goes to the negative side of the battery. The power to the turn signals comes from the colored wires, and unfortunately one of them is black which makes it easy to forget that it is a power wire....and not a ground.
The bulb is a 2 filament bulb. The short filament is the running light and is something like 5 watts. The long filament is the brake light and is something like 23 watts, and it has a center support to make it more durable....the support is not grounded and only provides support to the filament to keep it from wiggling and breaking.
For a 1987 bike the wiring diagram shows you should have a white wire with black stripes that goes back to the brake light. Run a jumper wire from the positive terminal and connect it there.....and if the circuit is good the brake light should come on. Then you can test the orange wire at the front brake switch to see if you have 12V positve power when the key is turned on.