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battery drain?
battery drain?
Any ideas would be of help ...im not good with electrics its all mysterious to me . PS the battery is new.
- schrader7032
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Re: battery drain?
'78 R100/7 '69 R69S '52 R25/2
Fast. Neat. Average. Friendly. Good. Good.
- jwonder
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Re: battery drain?
I need to find a "+1" button for the forum for up-voting answers.
If you need more help from what Kurt says let us know!
Vice President, Vintage BMW Motorcycle Owners
2022 BMW Friend Of the Marque
Long Island, New York
Re: battery drain?
Something like this is very useful. When selecting this type of meter make sure it explicitly states DC Amps.
Don
All on the road, going no where in particular in the Finger Lakes of New York
- vechorik1373
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Re: battery drain?
But IF you can't seem to find a source of the drain, then the voltage regulator may be bad. It MUST cut the generator out of the circuit, when the bike is shut down, or when the bike is idling, and not charging. Generators, unlike alternators, will try to turn just like an electric motor, if they are not cut out of the circuit when the key is shut off. That will drain the 6v battery pretty quick. Just something to consider. If you physically remove the generator from the circuit ( a quick and simple test is to lift the brushes off the commutator of the armature and insulate them from the armature (lift the brushes and put a slice of paper between the brush and the armature to see if the drain stops when the bike is off.) That will tell you there is a regulator problem if the drain suddenly disappears.
Technical Adviser, Former owner, Bench Mark Works
662 312 2838 cell 9 am to 4pm CST PLEASE!
Re: battery drain?
- Micha
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Re: battery drain?
Should the motorcycle not be in use for some longer period, please disconnect the battery
(so existing) to prevent current bleeding through the diodes of the regulator. Though, even a
disconnected battery will empty itself after a while.
R51/3 1952
Engine Nr. 529466
- pmtremblay
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Re: battery drain?
A +1 or other recognition button would be cool. There are so many discussion here I have nothing of value to add, but would like folks to know I appreciate the conversations. I get way more out of this forum than I can give back.
'66 R27
'22 G310R
- vechorik1373
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Re: battery drain?
On an original generator, with a electro-mechanical original voltage regulator, you cannot use a digital volt meter, because it takes repeated samples WAY to fast. The digital numbers will just tumble constantly. If you hooked up a charging system to an oscilloscope, and slowed time down with it, you would see that the mechanical regulator flutters, with the voltage constantly climbing and diving. The old time analog meter dampens this oscillation out, and gives you an average value as to your voltage.
And, with a correctly functioning generator, not only should you see 7.2 volts (not more, and not less) if you put an amp meter in the circuit also, you should see 1 amp.
The new solid state replacement regulators, do a much better job of current regulation. The power is steady state when viewed on an oscilloscope. This is much better for not only the battery, but the all bulb filaments also.
Bulbs do not like variations in voltage. It tends to make them fail. Of course, at idle, when the system is not charging, there is a voltage drop, and everything (except the magneto on a twin) is running off the battery.
Technical Adviser, Former owner, Bench Mark Works
662 312 2838 cell 9 am to 4pm CST PLEASE!