Norton Commando Wiring Diagram + Tri-Spark + Podtronics

Grant Tiller

This diagram includes BOTH the Tri-Spark Electronic Ignition AND the Podtronics combined Regulator/Rectifier unit.

Pre-1971 (ammeter in the headlight shell and Wipac Tricon type handlebar switch) PNG 3066×1841

Grant Tiller

1971 (three wires to the master switch) PNG 3066×1841

Grant Tiller

1972 onwards (four wires to the master switch) PNG 3066×1841

Grant Tiller

1974 MK3 Early Bikes – there were around 2,000 bikes that were built around the December 1974 timeframe that have three additional fuses that can be found in the headlamp bucket.

These bikes are also wired with the old Lucas 3AW 3 wire ‘silver can’ assimilator.

1974 MK3 (Early) PNG 3066×1841

Grant Tiller

1975 MK3 this is the most common configuration, and takes us through to the final Commando that rolls off the production line.

1975 MK3 (Original) PNG 3066×1841

Grant Tiller

1975 MK3 Canadian Market – there were legal requirement in Canada around the headlamp being on while the engine was running, so the wiring diagram includes changes needed (swapping out the Warning Light Assimilator 06-6393 for the Headlamp Warning Unit 06-6392). Note that a different Master Switch is also required.

This is covered in the Factory Wiring Diagram, by notes.

1975 MK3 (Canadian Market) PNG 3066×1841

Grant Tiller

This combination really makes for much simpler wiring on the Commando!


A couple of points about the way these diagrams have been drawn:

  1. Where the same colour wire goes in to and out of a single connector, that connector has usually been omitted from the drawing.
    It’s obvious on the bike, is easy to spot and easy to troubleshoot.
    Leaving them off the diagrams makes them a LOT easier to read, and considerably less cluttered.
  2. Wherever the earth or ground side of a component goes back to the battery, the drawing shows a red earth symbol:
    Grant Tiller
    In reality, this could be connected either to a red wire in the bike’s wiring harness (loom) OR it could be attached to the frame or engine of the bike.

    I have shown the red earth symbol each time in order to massively simplify the diagram, and make it a lot easier to understand for everyone.

    I have also coloured them red as a gentle reminder that these bikes are wired positive earth!

5 replies

  1. Thanks for the site, the wiring diagrams are brilliant and very helpful. Can you tell me what software they were made from, I would like to make one for my Triumph T160 Trident. Thanks

    • Thanks Simon,

      Currently using Paint.NET which isd free, but very time consuming!

      I tried CanvasGFX but during testing found an issue with grouped graphics dancing on the page – not good when you are drawing diodes or expect your wires to join up.
      I was less than impressed with their support department, who wouldn’t acknowledge the issue until i sent them several files and videos of it actually happening.
      If and when they fix it, i will switch over, as it’s an otherwise good product – and the only one I have found that lets me draw wires how I like to see them!

  2. I have a 1977 Norton Commando MK 111 I have fitted a podtronics control unit but have no charge what do I have to remove to convert this to make it work I have removed all the original parts including the zener diodes and charge rectifier control but have left the capacitor in place. I also have fitted a pazone ignition set. Do I also have to disconnect the small connecting diode marked with w/lamp alt, etc,
    If you could give me some advice it would be most helpful.
    All the alternator part are new and have the correct air gap between stator and rotor.

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