Thanks, the under seat wiring is another rats nest. I'll see if the blue mystery wire actually is connected to the headlight relay through the blue/black wire. I'm not sure it does though as I'm not getting any voltage at all at the end in the headlight shell. I've spliced the instrument lights into the brown wire in the connector with the wires for the neutral light. If I can get power through the blue wire, I can easily remove my splice.If you study a '79 Special wiring diagram, you'll see the blue power wire from the instrument lights runs back through the harness and ties into the L/B coming out of the headlight safety relay and running to the RLU. When the headlight relay is tripped and sends power on the L/B to the RLU, it also gets sent up the blue wire to light the instruments.
OK, I think the easiest way would be to just run a new wire from the instrument wires back to the safety relay. I tried checking continuity on the mystery wire to the relays at the rear and no joy.If you study a '79 Special wiring diagram, you'll see the blue power wire from the instrument lights runs back through the harness and ties into the L/B coming out of the headlight safety relay and running to the RLU. When the headlight relay is tripped and sends power on the L/B to the RLU, it also gets sent up the blue wire to light the instruments.
That's probably what I'll end up doing for now, that is running tube from the carb vac port to the carbs. I would rather have non vacuum petcocks, but since this is what I have, I'll use them. I got the tank clean using white vinegar, so I guess I should take the petcocks apart to make sure there's no gunk inside.Vacuum petcocks without vacuum will only flow on 'Prime' position, which is the whole tank, including reserve, so is of little use out on the road, leaving you high and dry.
I don't see any reason why you can't T into the crossover tube and run it from the inlet vacuum ports on the spacers.
Or, just run each petcock vac port to its own carb vac port.
I would update my profile with a list of bikes I have, but can't figure out how yet.
Well, another day of 2 steps forward, 1+ steps back. I played with the mixture screws starting at 2 turns and worked 1/2 turn at a time. Still having issue with hesitation and hiccup until I got to 3 1/2 turns. Went up and down the road and bike ran really pretty well. Hesitation was barely noticeable and feeding the clutch out from a stop was fine. Put the bike back in the garage and this morning when I opened the door, gas was dripping out on the floor. The petcocks are the vacuum operated type and they were in good condition. Before I mounted the tank, I put gas in it, and let it sit. All seemed well until yesterday. Fortunately no harm done. I think possibly one of the float valves stuck also, but I didn't think the petcocks would allow gas flow without the engine running. Anyway, the vacuum stuff is going away. I have non vacuum petcocks and the seals I hope will stop the leaks coming.
I'm taking a break for a week and everything should be here when I get back.