Rewiring my bike!

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So i'm going to build my own wiring harness on my 74 Commando. I've got a PodTronics regulator/ rectifier and a Boyer Brandsen Ignition. I'm elliminating the turn signals and running a 3 position ignition switch in the headset and placing a kill switch in leau of the turn signal warning light on the headlamp.

Is the warning light assimilator a completely separate part that I need to run in line with the Podtronics, or does the Podtronics have it built in? Also, is the ballast resistor part of the ignition uint? Or is that something i need to install?
.
 

L.A.B.

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If you intend to fit a Boyer Bransden ignition system then the ballast resistor is no longer used as the two ('74 should be 6V) coils are then wired in series.

I don't think the Podtronics units have a charge warning light function although Boyer 'Power Box' type control units do.
 
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does the podtronics need to be wired DIRECTLY to the battery? or can it be ran into a junction with all of the other wires running to the negative? I want to have only one wire running to the + and one to the - on the battery. The rest of the wires I want to set up in a terminal board..
 

L.A.B.

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I can't see any need for the Podtronic unit to be connected directly to the battery, and I think it should be protected by the fuse (if you intend keeping the single fuse system), so anywhere between the fuse and the ignition switch should be fine.
 
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Make sure your kill button is really fine. Better yet add a relay to step down the amps to this KILL switch.Headlite relay helps too.
Also add grounds. Headlight, engine, Pod, coils all tied back to the frame near the battery and then to the battery.
 

L.A.B.

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I'm not quite sure I'd want to route the charge circuit across the kill switch (personally). I think I would go straight to the ignition switch terminal.

I don't see (from the drawing) any reason for the ground wire that comes from the ign. sw?
 
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I'm not quite sure I'd want to route the charge circuit across the kill switch (personally). I think I would go straight to the ignition switch terminal.

Yeah, thats what i was kindof thinking. I was thinking of running it straight to the battery, but then it would always be running a current, it seems. I could run it off of the accessory (brn) circuit.

I guess you right about the grnd from the ignition. It probably wouldn't work at all, for the accessory circuit would it? The current would go straihgt from the ground to the battery, since thats the path of least resistance.
 
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Make sure your kill button is really fine. Better yet add a relay to step down the amps to this KILL switch.Headlite relay helps too.
Also add grounds. Headlight, engine, Pod, coils all tied back to the frame near the battery and then to the battery.

If I wanted to step amperage down, wouldn't I just want a resistor?? Or are you saying to get a relay WITH some sort of resistance?? However, if I were to run the charging circuit straight through the accessory circuit, leaving the Ignition module the only thing in the ignition circuit, I could then just run a resistor right before that switch. But, wouldn't that mess up the amount of current required to operate the Ignition??
 

L.A.B.

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By using relays you help to reduce the load across any switches which for a headlamp or horn is a good idea (and not because you need to ADD any resistance).

You could run both the ignition and the Podtronic unit from the brown wire circuit? Unless you intend to have a 'running on ignition only' ignition switch position, and 'ignition + accessories' position? The Podtronic unit could then be connected in the more normal location (between the fuse and the ignition switch) as it doesn't really need to be isolated when the ignition is switched off.
 
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By using relays you help to reduce the load across any switches which for a headlamp or horn is a good idea (and not because you need to ADD any resistance).

Are you saying to run the coil of the relay in series with the circuit? Rather than running a switch to actuate a relay that then operates the Horn or the Lights??

My understanding of relays is that they are used when a different voltage is required for operation than what's used to actuate it..for instance, if you have an AC circuit that needs to be actuated by a DC crcuit, you would run a relay. Then you would energize the coil with DC voltage which then actuates a switch. Through that switch you can run the AC voltage to the appropriate circuit. The same goes for circuits of different voltage or current value.


So I can see how running the current through that coil would affect the load running into the Kill switch or the Light switch. But, if thats the case I could simply use a light.. That would be kinda sweet, a little light pops on whenever I use the horn.

I guess I could run the switch of the relay and the coil in parallel?? I'll have to go back to the ol' books for that one.

Just for reference of where I'm coming from, I'm an Aircraft Instrument Technician. So, I understand elctricity very well. This whole positive ground thing is new to me, but relatively simple to figure out. It just means that the frame of the bike would be charged, which is creepy and weird, but thats ok. As far as relays and large scale wiring, I'm not well versed because I learned all of that stuff about 4 years ago and it's since been pushed to the back of my mind.
 
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There's only one reason for positive earth. Spark plugs are just a bit better with it this way. Everything else runs worse. The relays we are talking about keep the volts the same and step down the amps. So keyed ing. switch, light switch on top of the headlight, kill switch, horn the list goes on anything you wish to protect.
 
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I don't see (from the drawing) any reason for the ground wire that comes from the ign. sw?

The red wire is meant for + to the battery. This ignition switch is one that I have from a Honda cb750. It's just the right size to put in the headlight bucket in place of the switch.

Is there really any reason to have the positive from the battery run into the Ignition switch?
 

L.A.B.

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These relays are just electrically operated switches that are capable of handling higher Amps better than the original switches can, so the original switch and wiring can be used to operate a relay. The high electrical load is then handled by the relay and not the switch.

The advantages of using relays being that there should be less Voltage drop in a higher Amp circuit like headlamp or horn (and the horn may actually work properly!) and the original switch contacts last longer and therefore should operate more reliably.

------------------------------------------------
Ignition ground wire.

Unfortunately your drawing doesn't show the internal ignition switch connections so I'm not quite sure what your trying to do?

But I cannot see that there's a reason for ANY of those wires to have a ground connection (maybe worth re-checking your circuits against the original Commando wiring diagram?)?

If I were to take a wild guess that you intend brown/white to connect to red (and be isolated from the battery feed and accessory wires?) then that would (I think?) short circuit the output from the charge circuit, and the Boyer unit would be wired to run from the alternator output when it should be operating from the battery circuit?

In order for the charging system to charge the battery then it needs to be connected directly to the battery circuit, so needs to connect to either the black or brown wires (in your diagram).

So (as I see it) the Pod. black wire should connect to the battery feed wire somewhere between the fuse and the ign.sw.?
Or I suppose it could be connected to the accessory wire if that circuit is live at all ign.sw. 'ON' positions?
And the Boyer unit connected to the battery circuit (accessory wire? or directly from the ign.sw.?).
 

Ron L

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I concur with all the comments about using relays. I have relays for headlights, Boyer feed/kill switch, and horn on my Interstate. Anything to eliminate voltage/current loss on the Lucas switches. In addition I mounted a small 4 circuit fuse panel, feed it from the battery and fuse headlights, ignition, and running lights/accessories separately. This uses blade-type fuses which are much easier to find if you are stuck by the side of the road.

I use Japanese copies of the Bosch style relays, they are reliable and cost about $1 apiece.
 
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Yeah, now that I'm looking at it again I'm starting to see the problems. That's what drafts are for, eh?

Anyways, I don't plan on using the bulky Lucas switches. I'm going to do away with the entire switch assembly on the right side and put a Brembo master cylinder in it's place. On the left side, I want a headlight control switchand a horn button. Like I said before, the kill switch would go in the middle of the 3 "warning" light holes. All of the switches are going to be new and hopefully stronger. The relays are a good idea, especially for the headlight.

I had to wait until i came to work today to check the continuity on my ignition switch and it is way different from what i thought it was going to be. I need to revise my little schematic quite a bit now. Back to the drawing board.
 
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