A decent Norton Commando upgrade is to move from the original points-based ignition system over to Electronic Ignition.
A popular unit these days is the Pazon Sure-Fire – it’s a great price, simple, reliable and comes with a very good warranty.
However, Pazon also make a fully digital version called the Altair.
This models boasts an improved map (optimized advance curve) that helps with engine idling and cold starting.
It also operates down to 6 volts, so gives you a chance when the battery is getting tired, and is also a perfect fit for Electric Starter conversions!
The Pazon electronic ignition system uses a concept called “wasted spark” – with the two coils wired in series, they are energized together on every rotation of the camshaft.
You’ll note in the wiring diagrams below that the Ballast Resistor and Condensers have been removed as part of the conversion to Electronic Ignition.
It’s worth noting that the wiring color scheme is different to the Pazon Sure-Fire (and the Boyer Bransden)
I find this a bit stupid to be honest, as although the wiring is covered in their installation guide, I see no reason why it should be different to the Sure-Fire (and Boyer Bransden)
It can be confusing for some.
A copy of the Pazon Altair Installation Guide can be found here
Having said that, the color coding of the wiring is simple enough:
Cable Color | Description |
---|---|
Red | this is the positive feed to the Pazon Altair, and is usually picked up from the red cable that goes to the Coil positive terminal |
Black | this is the negative feed TO the Pazon Altair it joins in to the White/Blue cable that used to feed the Ballast Resistor that you are removing. As standard, this goes up to the big connector block under the tank, where it’s joined to the White/Yellow that is the kill switch on your left side handlebar switch cluster. If the white/yellow is long enough, you can connect the black wire of the Pazon Altair directly to it! |
Violet | this is the negative supply FROM the Pazon Altair TO the coils |
White/Black Violet/Red White/Red | these go from the Pazon black box (they call it the Ignition Module) down to the Stator Plate (which they call the Trigger Assembly) that sits behind the points cover. |
Pre-1971 (ammeter in the headlight shell and Wipac Tricon type handlebar switch) PNG 3066×1841
This is available as a PDF too – it can be downloaded here.
1971 (three wires to the master switch) PNG 3066×1841
This is available as a PDF too – it can be downloaded here.
1972 onwards (four wires to the master switch) PNG 3066×1841
This is available as a PDF too – it can be downloaded here.
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
This is available as a PDF too – it can be downloaded here.
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
This is available as a PDF too – it can be downloaded here.
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
This is available as a PDF too – it can be downloaded here.
NOTE:
A couple of points about the way these diagrams have been drawn:
- Where the same color cable 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. - Wherever the earth or ground side of a component goes back to the battery, the drawing shows a red earth symbol:
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 colored them red as a gentle reminder that these bikes are wired positive earth!
Categories: Aftermarket Upgrades, motorcycles
Thanks for the wonderful information you have provided on this website. The simple construction, yet complex workings of the Lucas systems from the alternator era have really been made clear.
My project is a 62 Atlas that has an abomination of a wiring loom. Household wire nuts lumped all the lighting together, bypassing the switch. Some no-name regulator replaced whatever was there in the first place.
I plan to upgrade to 12 volts with Pazon ignition, and two wire alternator using my existing stash of parts. I may upgrade the brake light switch to include something to work on the front!
Some good upgrades planned Bill!
One thing to watch with the front brake light switches is that the inline switch option which fits on the brake cable can often result in a spongier feeling brake.
…a decent alternative is to think about fitting a microswitch under the brake lever on the handlebars instead.