Norton Commando Wiring Diagram + cNw Electric Start Conversion

Grant Tiller

Matt Rambow and his team at Colorado Norton Works make some beautiful stuff, and their latest creation – an Electric Start Conversion for the pre-MK3 Norton Commando is no exception.

The cNw kit, found here is actually very reasonably priced at $2,495 if you consider that it includes a belt drive primary.

Grant Tiller

As always with Colorado Norton Works, the quality of the fit and finish is second to none.

If you don’t want a highly polished finish, there are option for satin and matt black too.

Grant Tiller

Matt supplies a starter button with his kit, as the quality of the original switches were dubious when they were new. That makes it difficult for Matt to support, and guarantee the reliability, hence shipping his own.

However, of the people I have spoken to, most want to use the original handlebar switch gear, and make use of the ‘spare’ button that Norton themselves never got round to using (the MK3 used different handlebar switches)

Here follows the Norton Commando pre-MK3 wiring diagram with the addition of the Colorado Norton Works Electric Start Conversion

The 1971 and 1972 onwards diagrams use the original Lucas switch gear.

The 20M3 bike is not a good candidate for an electric start conversion, as the points location does not give ample clearance for the starter motor assembly to be mounted.

If you want to fit electric start to an older bike, either fit a later camshaft and timing cover so that you can move your ignition to the front of the bike, look into a crankshaft mounted ignition trigger, or fit a later engine.

Anything is possible of course, but i would suggest that the engineering work/re-work involved would make it non-viable for most, and probably not financially sensible either.

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

I will post a diagram that includes Tri-Spark electronic ignition and Podtronics reg/rec too, as these are upgrades that Matt recommends should go hand in hand with his Electric Start kits!


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!

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