1971 Norton Commando Ignition Switch

Hi Norton experts,

I have a 1971 Norton Commando, and both the headlight and brake light have recently stopped working. I'm starting my troubleshooting at the ignition switch. Hopefully my photos in the link work.

According to Grant Tiller's wiring diagram, the bike originally used a 3-position ignition switch. However, after removing mine, it appears to have been upgraded to a 4-position switch—though it doesn’t look like a standard Lucas type.

The wires connected to it are:

• Brown/Blue
• White
• Brown/Green
• Blue/Yellow

The issue I'm facing is that the current switch uses single male spade terminals with two wires sharing a single female spade. The replacement Lucas switch which I'm looking to buy (30552 – Ignition & Light Switch for Norton/Triumph) uses individual male spades for each connection.

My question: can I separate the wires, install individual female spade connectors, and plug them directly into the new Lucas ignition switch?

Thanks in advance for your help!

TheFlyingKiwi said:

My question: can I separate the wires, install individual female spade connectors, and plug them directly into the new Lucas ignition switch?

Click to expand...

No, that makes no sense to me as you should only need to connect each double wire to one of the double switch terminals which would be correct.
A 1971 model shouldn't have the blue/yellow so it's possibly been rewired to the later standard.
It should in any case be a four position switch Park-Off-Ignition-Ignition and lights.

Thanks for the reply LAB, that makes sense re the terminals. It must have been rewired at some stage with an aftermarket ignition switch.

Thanks

TheFlyingKiwi said:

According to Grant Tiller's wiring diagram, the bike originally used a 3-position ignition switch.

Click to expand...

That is not correct, it should still be a four-position switch but would only have had three terminals, no blue/yellow or terminal 4 so the headlamp had to be switched off at the headlamp switch in order to use the parking lights which meant anyone could walk up to the bike and switch the headlamp on. This was considered unsatisfactory so the headlamp was eventually powered from the ignition switch through blue/yellow and therefore unavailable at 'Park'.


This change apparently occurred at 202116 during 1972.