I have a slow discharge at my battery, which runs my battery dead overnight. I hook my volt meter to the battery, and every 30 seconds to 1 minute,I can see the battery drop 1/100 of a volt. Example, battery reads 12.66 volts, and you can see it drop to 12.65, then in another 30sec to 1min, it will drop to 12.64, and will continue to do so. I disconnected the ground cable, and the battery stayed rock steady. ALSO!!! Yesterday, I went to go for a ride, and the battery was dead. Starter only clicked. I thought maybe I left the key on or something, so I put the charger on the bike for about 15 minutes. I fired the bike up, and decided to check the charging rate. It was in the 12s with the bike revving 3500-4000 rpm. Def. not working properly. I figured maybe because the batt. wasnt fully charged may have possibly been the problem, so I went for my ride.Had no problems! I put a battery tender on the bike overnight to get a full charge, so I could check the charge rate without any doubts. The tender was not indicating the batt. was fully charged this morn. and I could hear the battery charging, so I pulled the tender off, and went to fire the bike. A click was all I got! I put my regular charger on the bike, and at 2 amps. After about 1/2 hr got around 13v at the batt., and noticed the discharge. Thoughts??????
Slow battery discharge problem
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naughtyG
Well-Known Member
Dead battery. They short inside and go. Most likely I think!
one2dmax
Well-Known Member
Could be. A fully charged battery is normally 12.60 Volts (2.1v per cell). BUT, they tend to take an hold a small overcharge. But, i'd wait to see if it goes much below that. Keep also in mind that a battery with 12.43 volts is considered discharged.
OK. I left the volt meter hooked up for an hour over lunch. The volts dropped to 12.39. I un hooked the battery,and put the meter back on.The volts have now recovered a bit,and are sitting at 12.47 in 20min. There is definately a finedraw somewhere on the bike
Put your meter across between your negative batt cable and the frame. Set it to read amperage to see how much draw you have with the key off...etc... You may have a small short somewhere not large enough to blow a fuse, or smoke any wires.
What's your harness look like? Any prior hacks, splices, or add-on electrical stuff?
One thing about it: You are going to have to tune up your charging system - soon - if it's only throwing "12s" knowing your battery is not fully charged and needs to be catching up.
What's your harness look like? Any prior hacks, splices, or add-on electrical stuff?
One thing about it: You are going to have to tune up your charging system - soon - if it's only throwing "12s" knowing your battery is not fully charged and needs to be catching up.
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Rusty McNeil
Well-Known Member
Another way to tell if its a system drain is to disconnect the ground (or positive, doesn't matter which) from the battery and put your Meter (set in amps) in series with the battery making any drain current flow through the meter.
Set the meter on the highest current range it has, then you can start stepping the range down to get more resolution on the meter as you discover just how much of a drain there is.
Using the ammeter method will eliminate internal battery decay or discharge and only show you true amp draw OUT of the battery.
Using a voltmeter set on volts is gong to show you battery decay even if its not a system drain. And Sean's right about the values. I wouldn't trust the voltmeter
Method a whole lot cause for maybe the first 24 hours after shutting the bike off the battery voltage is going to be decaying back down to its natural state of around 12.65-12.7 for a lead acid battery ((higher if its an AGM) regardless of any system drain.
I don't know how much of a drain is normal, never checked one of these bikes. Shouldn't be much though. Most cars have close to 50-75 milliamps, but modern cars have electronics that are powered up even with the key off and doors closed.
I wouldn't expect to see any amount of drain on a Vmax. Anything you see would be "not by design", but insulation integrity and dirty switches, contacts etc will always give you something more than 0 milliamps, 5-10 milliamps shouldn't hurt you though as long as its ridden regularly and charging well.
If you see something its time to start pulling fuses and or disconnecting stuff to see if you can narrow it down.
Don't turn on the key on while your doing any of this, its possible to "over range" the meter and blow the fuse in the meter.
It does sound like your not charging well either but that could be simply cause your battery won't take it, not necessarily because the charging system is inadequate. R/R output values into a poor battery aren't going to mean a whole lot because they'll be different than a solid condition battery.
Set the meter on the highest current range it has, then you can start stepping the range down to get more resolution on the meter as you discover just how much of a drain there is.
Using the ammeter method will eliminate internal battery decay or discharge and only show you true amp draw OUT of the battery.
Using a voltmeter set on volts is gong to show you battery decay even if its not a system drain. And Sean's right about the values. I wouldn't trust the voltmeter
Method a whole lot cause for maybe the first 24 hours after shutting the bike off the battery voltage is going to be decaying back down to its natural state of around 12.65-12.7 for a lead acid battery ((higher if its an AGM) regardless of any system drain.
I don't know how much of a drain is normal, never checked one of these bikes. Shouldn't be much though. Most cars have close to 50-75 milliamps, but modern cars have electronics that are powered up even with the key off and doors closed.
I wouldn't expect to see any amount of drain on a Vmax. Anything you see would be "not by design", but insulation integrity and dirty switches, contacts etc will always give you something more than 0 milliamps, 5-10 milliamps shouldn't hurt you though as long as its ridden regularly and charging well.
If you see something its time to start pulling fuses and or disconnecting stuff to see if you can narrow it down.
Don't turn on the key on while your doing any of this, its possible to "over range" the meter and blow the fuse in the meter.
It does sound like your not charging well either but that could be simply cause your battery won't take it, not necessarily because the charging system is inadequate. R/R output values into a poor battery aren't going to mean a whole lot because they'll be different than a solid condition battery.
Rusty McNeil
Well-Known Member
Is that the lowest scale on the meter?
No. I also checked it on other ranges as well,and still got nothing. Strange...I had my meter on volts, and hooked to the battery for over 2 hours, and it stayed steady with no voltage drop.Hooked the battery back to the bike,and voltage very slowly dropped 1/100th at a time??? I hooked the charger up to my battery again, and it just keeps on charging away! Never shows that the battery is fully charged, and shuts itself off, even though the meter says its over 13v.
DMAN999
Well-Known Member
I just put my Multi-meter on my Battery (it's on the bike) to check it and it was at 12.97 and stayed there for the 5 Minutes I left it with no leak down.
And it hasn't been charged in weeks.
It sounds like something is causing yours to drain since it only leaks down when connected to the Bike.
I'd check all you electrical connections one by one and find out what is causing that drain.
And it hasn't been charged in weeks.
It sounds like something is causing yours to drain since it only leaks down when connected to the Bike.
I'd check all you electrical connections one by one and find out what is causing that drain.
Tex85
Well-Known Member
Based on your last post it sounds like it might be worth getting the battery tested assuming the auto-shutoff feature on your charger is still working properly. Most auto parts stores will test it for free and that would at least rule out or confirm the possibility of a battery problem. It would certainly be a lot easier than chasing down every possible item that could be drawing on the battery.
one2dmax
Well-Known Member
As pointed out try to remove one fuse at a time to see if the voltage drain stops. Don't forget there is the main fuse as well as the 4 regular fuses.
Will try the fuse pulling tomorrow. Two battery chargers were used on that battery. One was a battery tender,and the other a car battery charger with 2, and 15 amp settings. Neither setting would shut off, neither did the Battery tender
Rusty McNeil
Well-Known Member
.
Rusty McNeil
Well-Known Member
One other thing I though of. Some lower quality Digital meters, or older analog meters (the ones with an actual moving needle) can act as a load all by themselves. Within resultant voltage decay. This alone can cause your voltage reading to decline as well. Not saying that's what is is. But it is a possibility.
sdt354
Well-Known Member
Charge the Battery to full capacity. Leave everything connected. Unplug the the red wire from your r/r (left side cover) and retest your battery after sitting over night.
Steve-o
Steve-o
Thank-you. Imhave also ben doing some searching on this issue, and it is not uncommon. Found some more tests I can do as well! Without this forum, I would be lost, as these Max' are a different breed!
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