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Hi have a problem with over charging I have a typanium unit hook up to my battery and it is overcharging the battery 17 18 volts all over the place is this due to a bad typanium or do I have it hooked up backwards positive ground system anyway if it is it should I switch to a Podtronics are they better I have been blowing front lights out but not back one so I put a meter on it and it was showing 17 19 volts nothing consistent all over the place could it be the rotor etc...

help appreciated

What kind of bike do you have?

I`m not familiar with the typanium unit unfortunately. Don`t think this will help you much, but on A65 you problem could be a default zener diode. Or if you have upgraded your system maybe you need two zener diodes to hold the watts down. How much is there with full lights on?

Don`t think it`s the rotor, your problem would be the opposite if the rotor was weak.

Good luck, and you`ll get better answers soon :-)

the bike is a 1969 BSA Royal Star

Sounds like the tympanium is defective or not wired up correctly. Don't know if Pods are any better. I've got a tympanium on mine.

In addition to what Alex suggested, does the Tympanium actually have a good ground? What you have told us points to a problem with the charge control unit.

Do a search on this site on grounds. There has been a lot posted. Grounding is more than hooking the battery up to the frame with a wire.

Which is better? Probably which ever one you have installed and is working. Alex has a Tympanium he is happy with, I am happy with Podtronics. Both do the job and do it more efficiently than the stock rectifier/diode.

Hey guys,

What should a properly working zener regulate the voltage to? I got 14.9 volts with the headlight on high at about 4200 rpm on my 69 Firebird.

Thanks,

Touch high but not unusual with a zener, especially an OLD zener. 14.5V is typically the normal high end on a 12V charging system.

Before binning it, check your ground at the Zener. Not a bad idea to run a dedicate ground from the zener to the same ground point the battery uses, catch the engine at the same time. Also clean the zener and it's mounting area on the heatsink. Then test it again.

Makes sence. Had to do the same on my BMW R65.

Thanks,

Nortonc, even if the typmp turns out not to be regulating(duff), you could always put a zener across it's output and regulate it that way if it's wired +ve ground.