Being new to the whole bike thing, + ground, Ive been doing some searching about rewiring on the forum. After doing a recent fork rebuild, and removing the tank to find a disaster of wires, Im going to rewire. I am not using the stock switches any longer, so Ill be making a custom harness. Ill be going with the full sparx alt, tri spark ign, just to get the bike in top shape. Have any of you done a 2 harness setup? Meaning making one harness solely for the purpose of ignition, and the 2nd harness for lights and accessories? I feel this would be a easier job to tackle, and troubleshoot if any problems arose. Also is there really any plus to going neg ground? Or would it simplify my harness even more?
Wiring harnesses
- Thread starter Vulin
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I'll be watching this thread as I'm starting the same job you are and am not quite sure what to do. I've got two weeks to get things going so I have to step on it as I've been putting this off for a week or two now. I'm also using a Tri Spark and Sparx charging system.
Coco,
I don't know if this will help, but think of your electrical system as a closed loop pressurized water system. The battery being the pump and the wires being the pipes. Just remember, electricity has to have a return path to it's source (battery). In the case of your Norton, the frame is the return path, i.e. ground, unless you provide another conductor. I apologize if I'm stating what you already know. It's just that I noticed some trepidation with your wiring project.
BTW, I get up your way once in awhile. I have a good friend in Indian Head, SK. Unfortunately, he knows very little about wiring Nortons.
I don't know if this will help, but think of your electrical system as a closed loop pressurized water system. The battery being the pump and the wires being the pipes. Just remember, electricity has to have a return path to it's source (battery). In the case of your Norton, the frame is the return path, i.e. ground, unless you provide another conductor. I apologize if I'm stating what you already know. It's just that I noticed some trepidation with your wiring project.
BTW, I get up your way once in awhile. I have a good friend in Indian Head, SK. Unfortunately, he knows very little about wiring Nortons.
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I designed and built a new loom for my heavily modified Mk3 (electrically speaking) that preserved positive ground ONLY because I wanted to preserve the existing assimilator and could not get a response from this (or any) forum as to whether the assimilator would function on negitive ground. I'm happy to share the harness diagram (field tested), and would be equallly happy to do the conversion and share the modified diagram if I could get anyone out there to confirm that the assimilator works with negative ground.
The harness diagram is quite clean, with no unused wires or connectors, and takes 8 hours or so to wire up. Original wire coding was followed. Surely someone has made this assimilator test?
Les?
The harness diagram is quite clean, with no unused wires or connectors, and takes 8 hours or so to wire up. Original wire coding was followed. Surely someone has made this assimilator test?
Les?
I would love to see the diagram. Thinking it over, I wont be doing much for lights, and would also like to preserve the + ground setup. I wont be using colored wire, Im used to working around aircraft where all the wire is white. So i will be making labels with clear shrink tubing for all wires to label them.
Vulin said:
Hey Steve. I think it's a good Idea to run a dedicated Ignition system through a relay. It's not as complicated as it sounds and it avoids the igntion switch, connections and the kill button if you do. This is Tony Foale's take on it.
http://www.tonyfoale.com/Articles/Ignition/Sidebar.htm
I did a lot of silly stuff with the electrics on my bike. I'll get some pic's together. It rains alot where I live so I was tired of the dodgey harness.
Ron L
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Why not wire up your own test circuit? Certainly the two AL terminals won't change. The WL terminal simply provides a path to ground for the warning light (which has a separate 12VDC feed). The IGN and E are feed and earth respectively. If it works, then you can tell us. If not, and you still want to convert to negative ground, use a voltage switch device to turn the lamp on or off. These function with either negative or positive ground and are available from Al Osborne (AO services), RGM, and others.
Do you have the Canadian "lights on ignition" version? Or a rest-of-the-world 3AW?
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Ron,
Thanks for your response. My Mk3 is the US version with an aftermarket 4-position switch and a new loom. I was aware of the simple solid-state switches around, but was hoping to use the existing assimilator. I'll do the conversion this winter, when I move the butt-ugly horn to a more discrete location. If the assimilator floats and WL must be referenced to ground, then the only options I see are (1) do a dumb -12v=>+12v swap on IGN leaving all other connections the same, or (2) run +12v to GND and ground to IGN, which preserves the internal polarity. In either case, I'm likely to smoke the assimilator, and prefer to wait until the end of riding season to try it.
Thanks for your response. My Mk3 is the US version with an aftermarket 4-position switch and a new loom. I was aware of the simple solid-state switches around, but was hoping to use the existing assimilator. I'll do the conversion this winter, when I move the butt-ugly horn to a more discrete location. If the assimilator floats and WL must be referenced to ground, then the only options I see are (1) do a dumb -12v=>+12v swap on IGN leaving all other connections the same, or (2) run +12v to GND and ground to IGN, which preserves the internal polarity. In either case, I'm likely to smoke the assimilator, and prefer to wait until the end of riding season to try it.
Ron L
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There is a electrical diagram on the NOC website for the solid state Mk3 assimilator. It has a transistor in the circuit, but my limited exposure to electronics isn't sufficient (more accurately my memory isn't sufficient) to recognize if polarity reversal is possilbe. Perhaps one of our electronics gurus can look at the diagram and tell us?
http://www.nortonownersclub.org/
Go to Technical Information, then Electrical, then Warning Light Assimilators.
Ron
http://www.nortonownersclub.org/
Go to Technical Information, then Electrical, then Warning Light Assimilators.
Ron
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rick in seattle said:
No, I haven't tried that, as I've never found it necessary to change the polarity of any of my bikes that have +ve earth/ground.
I don't actually remember if any one has said they changed the assimilator's polarity before?
However here is the electrical diagram of the 850 MkIII assimilator, as the unit apparently contains a transistor and two diodes, then I'm not sure it is possible?
Perhaps our electronics experts could give their opinions?
http://www.nortonownersclub.org/technic ... etail.html
There are other charge warning units on the market that will work.
http://www.aoservices.co.uk/data/lvs.htm
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pelican said:
It is a two pin socket that can be used to supply 12V battery power to any accessory up to 17.5 Amps such as a lamp or "radio or shaver" (according to the riders manual), or alternatively it can be used as a connection point for a battery charger.
pelican said:
I think the solenoid wires stay as they are, the heavy wires would not have to be changed.
Also, the starter motor rotation isn't affected by polarity.
L.A.B. said:rick in seattle said:
No, I haven't tried that, as I've never found it necessary to change the polarity of any of my bikes that have +ve earth/ground.
I don't actually remember if any one has said they changed the assimilator's polarity before?
However here is the electrical diagram of the 850 MkIII assimilator, as the unit apparently contains a transistor and two diodes, then I'm not sure it is possible?
Perhaps our electronics experts could give their opinions?
http://www.nortonownersclub.org/technic ... etail.html
There are other charge warning units on the market that will work.
http://www.aoservices.co.uk/data/lvs.htm
Swap the Earth and WL leads for a negative ground system. The ignition terminal will have to be grounded.
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Ron and Les,
Thanks for the diagram. The Mk3 assimilator shown here is hopelessly positive ground. To operate in a negative ground system, the diodes would have to be reversed, and the pnp transistor changed to an npn. IGN and GND cannot simply be reversed, as I had hoped, since the transistor is triggered from the sum of the positive rectified alternator waveform and the IGN (switched -12v battery) voltage.
The remaining solution is, as many of you have reminded me, an aftermarket switch. Since the only real demand for negative ground is use of LEDs, and all of my add-on goodies (Pazon, SPARX rectifier,SPARX 3-phase alernator) are perfectly happy to exist in a positive ground world, I'll dance with who brung me and stay with the original polarity.
Concerning the original starter relay, the exciter coil is internally wired to the case, i.e. hard wired to ground. These relays usually have a diode-protected exciter circuit, so I would guess that it would not operate with reverse polarity. The output terminals would not have to be changed.
Thanks for the diagram. The Mk3 assimilator shown here is hopelessly positive ground. To operate in a negative ground system, the diodes would have to be reversed, and the pnp transistor changed to an npn. IGN and GND cannot simply be reversed, as I had hoped, since the transistor is triggered from the sum of the positive rectified alternator waveform and the IGN (switched -12v battery) voltage.
The remaining solution is, as many of you have reminded me, an aftermarket switch. Since the only real demand for negative ground is use of LEDs, and all of my add-on goodies (Pazon, SPARX rectifier,SPARX 3-phase alernator) are perfectly happy to exist in a positive ground world, I'll dance with who brung me and stay with the original polarity.
Concerning the original starter relay, the exciter coil is internally wired to the case, i.e. hard wired to ground. These relays usually have a diode-protected exciter circuit, so I would guess that it would not operate with reverse polarity. The output terminals would not have to be changed.
Rick,
Why wouldn't the pnp transistor work if the emitter is positive with respect to the collector? Then a positive base would turn the transistor off, no? While it's true the diodes would have to be switched with a npn transistor. Then the negative from the alternator would turn off the transistor.
Why wouldn't the pnp transistor work if the emitter is positive with respect to the collector? Then a positive base would turn the transistor off, no? While it's true the diodes would have to be switched with a npn transistor. Then the negative from the alternator would turn off the transistor.
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Had a quick look at this issue, and here's my take on it. It's about as simple as you can get
Ignition | Alternator | Lamp
___________________________
Off | No Charge | Off
Off | Charge | Don't care
On | No Charge | On
On | Charge | Off
I've put in a relay here for really low parts count and it should be pretty reliable.
When the alternators running and the ignition is on, there should be about the same voltages on either side of the relay coil,
with the result that the relay will not be energised and the lamp will be off (lamp gets supplied via ignition switch by the way).
If the ignition is on and there is no zap from the alternator, the resistor will allow the relay to turn on, turning on the lamp.
I would use a sensitive relay (not, say, a horn relay) to keep the resistor values high and current wastage low.
If you want to use it for negative earth, reverse the diodes and the capacitor.
Ignition | Alternator | Lamp
___________________________
Off | No Charge | Off
Off | Charge | Don't care
On | No Charge | On
On | Charge | Off
I've put in a relay here for really low parts count and it should be pretty reliable.
When the alternators running and the ignition is on, there should be about the same voltages on either side of the relay coil,
with the result that the relay will not be energised and the lamp will be off (lamp gets supplied via ignition switch by the way).
If the ignition is on and there is no zap from the alternator, the resistor will allow the relay to turn on, turning on the lamp.
I would use a sensitive relay (not, say, a horn relay) to keep the resistor values high and current wastage low.
If you want to use it for negative earth, reverse the diodes and the capacitor.
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