Tympanium wiring

Sorry for asking what is probably a very simple question.

I installed a new battery today, and when checking the voltage it shows 12.5 with nothing on and 12.3 when the bike is running even over 3000rpm. I take this as not charging and start reading treads on where to start checking. When I get to the rectifier the PO has changed to a Tympanium unit. The way it is wired is both yellow wires from the Tympanium go to the corresponding two leads from the alternator, the red goes to the positive terminal of the battery (positive ground), and the black from the Tympanium also goes to the positive battery terminal.

From the Old Britts site it reads Tympanium (Black)...Existing Wires (Brown)...Function (B-,battery)

I take this to mean the Tympanium black should go to the negative battery terminal. Anyone know if that is correct? I'm just scared to fry something else if I'm wrong.

Thanks

You've a typo writing red and black both on + battery terminal.
All black wires should be attached to the negative black labeled battery terminal and all the reds onto the + labeled red side of battery. At 3000 rpm should see almost 14 V if not more. The yellow leads should show way over 14 v but I forget what in normal. Its pretty darn rare for a potted solid state Tympanium to go bad. That what runs my Combat last half decade, often with a flat old battery.

No typo, that is how the PO wired it both black and red from the tympanum go to the positive battery terminal. Just wanted to confirm my reading of the Old Brits info was correct that the black should go to the negative battery terminal like you stated.

Thanks

Ok then no charging would show up on meter, should be ok once black moved to -.

Thanks Hobot,

I moved the wire and have around 14volts, and the headlight is way brighter . I only put on 60 miles last fall when I got the old girl, looks like I was running on battery power only .

Arighty then made my day too getting one thing right but then again this was only a 50/50 poke in the dark. Bright lights on most Commandos still looks like a candle light parade at ralleys.

Ok, so I just bought a tympanium to replace my rectifier and Zener. I understand how to wire it up, but what do I do with the extra wires from the regulator (3 red wires bolted to the bottom) and the two wires down at the Zener. Do I leave the capacitor in place also? The bike in question is a 1970 750 Roadster.

72westie said:

what do I do with the extra wires from the regulator (3 red wires bolted to the bottom)

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Presumably, you meant the rectifier (as the Zener is the regulator)? If so, then re-bolt the terminals to the frame as they are earth/ground wires.

72westie said:

and the two wires down at the Zener.

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Those two wires can either be taped back to the harness or cut off and insulated.

72westie said:

Do I leave the capacitor in place also?

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Yes, the 2MC capacitor can remain connected.

Thanks! I had figured that's what I had to do with the wires. You are correct, I meant rectifier, not regulator.