Suspect Assimilator problem

73 850 Commando has been working great for 2 years. 100% stock and original. Lately my ignition light has been eratic. Sometimes comes on with key on, sometimes not. Bike starts easily and runs good. Voltage at idle is 13v, goes up to like 14.6 at higher RPMs. Very linear on charging it seems. If I start it and the light is off, raising the revs actually makes it turn on for some reason, and the light gets brighter with the revs as would be expected with the rising voltage. I think my charging system is working just fine and the assimilator is bad. No test for it in the clymer manual though. I've read while searching that they are prone to failure. Is there a specific test to validate assimilator function?

Thanks in advance.

They always were a rather frail device, best bet would be to fit an electronic replacement version,
Dave.

got the electronic assimilator from Old Brits. Plug compatible, fit right in, fired right up. light went out as expected. All is well.

Amazingly I ordered it monday, it shipped monday parcel post from Washington State to Florida. I got it wednesday. Amazing. I thought I'd be lucky to get it by the weekend.

Woo Hoo. I was happy. Had to take time off from putting the new hood on my MG TD to get the Norton back together.

Interestingly enough you can change out the assimilator without removing the tank so it was an easy replace.

Just a follow up.

I have received things from Old Britt on the second day all of the time. I think they must be close to a postal hub to pull this off consistantly.