could use some help with battery drain
Seasoned HDF Member
Joined: Apr 2011
Posts: 6,185
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From: W. Texas
lmao Dang now I gotta go find the Fluke.
ok for conversation and not to be argumentative .50 amp (half an amp) = 500 milliamps. in turn .05 = 50 ma. This comes from auto repair back ground and memory. If a meter is set to a 10 amp while maybe not quite as accurate I thought could read down to 00.00.
If the meter showed .2 that would be 200 ma where .02 is 20 ma
Ok time for another beer and get back to cooking and I'll refrain from sounding off.
The fluke is at the shop and I'm not riding or driving anyplace.
respects WP
ok for conversation and not to be argumentative .50 amp (half an amp) = 500 milliamps. in turn .05 = 50 ma. This comes from auto repair back ground and memory. If a meter is set to a 10 amp while maybe not quite as accurate I thought could read down to 00.00.
If the meter showed .2 that would be 200 ma where .02 is 20 ma
Ok time for another beer and get back to cooking and I'll refrain from sounding off.
The fluke is at the shop and I'm not riding or driving anyplace.
respects WP
Last edited by WP50; Apr 10, 2016 at 05:50 PM.
Seasoned HDF Member
Joined: May 2008
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From: South Carolina
WP, THC, obviously you guys are correct, I was using some fuzzy math, and an old brain....
But even 20ma seems high for a parasitic discharge, I would expect to see next to nothing on 89 model year bike.
But even 20ma seems high for a parasitic discharge, I would expect to see next to nothing on 89 model year bike.
Last edited by Dan89FLSTC; Apr 10, 2016 at 08:08 PM.
Dirt don't hurt
Joined: Jan 2011
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From: Haslet Texas
Other than a radio I can't think of anything that should be there and drawing amps with the ignition off.
Seasoned HDF Member
Joined: Apr 2011
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From: W. Texas
Every now and again I can get something right. Ol brain and fuzzy math I can relate to Sir
89 bike Yea 20ma draw seems high to me as well. Can't think of a thing that might draw that much other than he has something hooked up he hasn't mentioned. Other than the regulator. 20ma is on the upper side of what I'd want to see on a car or truck, then again 30 -50 ma draw is not uncommon on latter model vehicle's. then they have bigger battery's.
I don't see a radio memory being more than 5-10 ma at the most. Best guess would be around 2 ma.
Respects WP
Seasoned HDF Member
Joined: Apr 2011
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From: W. Texas
usually the diode in the regulator is bad switching the main reg wire to key on will stop the drain But the reg is on the way out and unless your doing this on the road chang the regulator
to confirm this - remove the neg term connect the test light between the two one on battery one end on the removed terminal and it should glow , not usually bright then remove the regulator plus wire the light will go off completely a volt meter also works
to confirm this - remove the neg term connect the test light between the two one on battery one end on the removed terminal and it should glow , not usually bright then remove the regulator plus wire the light will go off completely a volt meter also works
Seasoned HDF Member
Joined: Apr 2011
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From: W. Texas
WP
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Seasoned HDF Member
Joined: Apr 2011
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From: W. Texas
At this drain rate, for a 30AH rated battery, it would take 150 hours to run the battery down 10%. Assuming you read the current properly.
So, depending upon how long it takes for your battery to run down, and at what point you consider it run down....you might just have a bad battery.
Do, I'd suggest getting a full charge in the battery (12.7 volts). . Then disconnect both battery cables, and let the bike sit for the amount of time it normally takes for the battery to run down. If it runs down in this condition, then you need a new battery.
So, depending upon how long it takes for your battery to run down, and at what point you consider it run down....you might just have a bad battery.
Do, I'd suggest getting a full charge in the battery (12.7 volts). . Then disconnect both battery cables, and let the bike sit for the amount of time it normally takes for the battery to run down. If it runs down in this condition, then you need a new battery.
If I remembered how I' double ck just to see but it's late and I'm tired
WP
