‘75 Mark III red ignition light

I recently mostly finished a restoration of a ‘75 Norton Roadster. The one issue that remains is the red ignition light on the center consol. With the key in the ignition on position the red light does not show any light, but with the bike running the light comes on. With higher reves the light is brighter, and as the RPM’s subside the light goes out. It is opposite of how it should work. A while ago it did work correctly, but I replaced some wire, and replaced the warning light control unit. Is it the unit or did I wire it backwards?

Edgarr said:

A while ago it did work correctly, but I replaced some wire, and replaced the warning light control unit.

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That does tend to suggest it being the result of something you've done.

Edgarr said:

Is it the unit

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Could be? Do you still have the old one to try?
Is it the early Mk3 type silver can 3-wire assimilator or the later 5-wire solid state type? If so, is it the standard or Canadian type?

Edgarr said:

or did I wire it backwards?

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Again, could be? As we can't see it and don't know what you've done then it's difficult to comment.

I think the Canadian model Mark III were designed for red the light to come on when the bike was started to remind you to turn the Ignition switch over to "lights on". Mine worked every now and then and now not at all.

brokeneagle said:

I think the Canadian model Mark III were designed for red the light to come on when the bike was started to remind you to turn the Ignition switch over to "lights on".

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The Canadian assimilator charge warning light should also come on with ignition. If the engine is started with the ignition switch at the 'Ignition Only' position then the warning light should then continue to glow "inversely with [engine] speed" until the switch is turned to the 'Ignition and Lights' position.

http://britmoto.com/manuals/Manuals/850_man.pdf
Sections J8 & J9.