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Battery losing charge.

Discussion in 'Technical and Troubleshooting Torque' started by droy333, Mar 15, 2008.

  1. Its a brand new battery.

    I can jump start the bike and charge it up but when it sits it slowly loses its charge over time when connected to the bike (F series ZX6R).

    Bike is charging at 14.5V's at 4500 rpm. Regulator/Rectifier gets pretty hot.

    I've checked the resistance in the Regulator/Rectifier and all seems to be normal within the appropriate pins (accord to TFM).

    The bike seems to run ok but you can hear the difference when the battery if flat.

    I'm thinking it may be a Rectifier I need since they're just a bunch of diodes and because a diode is a 1 way component if it fails it could leak power back the opposite way but then the resistance would be off somewhat so I'm not too sure.

    After leaving it sit for a couple days and I try and start it again it sometimes lets out a crazy loud BANG when first trying to turn over (though it could be a key banger situation?). The bang doesnt sound good but the bike still runs as normal after you jump start it.

    Any ideas? Besides take it to a mechanic :p Any other components that could possibly be stealing my charge?
  2. All I can suggest is to hook up a multimeter in series with the battery & measure if there is actually any current flowing with the key off. Then start pulling fuses (if there is current draw) until you identify the offending circuit.
  3. its not losing charge THAT quickly though. Good idea.

    I've stripped it down to check out the wiring (last thing on the list usually). I found the negative wire for my charging system. Some of the wire is exposed (ie. the insulation is gone). This shouldn't cause a problem I dont think because the wire is still there and its connected. Might patch it up anywho.

    Any other ideas?
  4. How do you know it's the negative wire?

    How do you know other wires are not in a similar state? Insulation is needed to stop short circuiting to ground via any metal component.

    You really need to do the multimeter test via the battery terminals. They (multimeters)cost next to nothing and we can give you enough tips to find all you need.

    All the best

    Trevor G
  5. How do I know its the negative wire? Cause it attaches to the negative terminal on the battery. The wire comes out of a loom of wires which are taped up. I visually inspected the rest of the wires around that area.

    If i tested the resistance in the regulator/rec you'd automatically assume I have a multimeter and know how to use it....

    Something is leaking power I just figured someone may have came across this before? Maybe it is the regulator/rec but I dont have one to test it.

    If i charged the battery back up then unplugged the regulator then checked it every now and then would that be sufficient to test?
  6. As I said earlier -hook the multimeter in series with the battery & with the key in the off position, check for current flow. This will tell you if it is either a dead or dying battery, or if something is actually using current. Does the bike have an alarm?
  7. Its a brand new battery so it can't be dead or dying.

    With the battery hooked up and the bike off the currently slowly goes away (0.01v per minute or something). When the battery is not hooked up it might do that in 24 hours.
  8. Check for CURRENT flow. AMPS. Or milliamps. Then start unplugging stuff or removing fuses to find out where it's going.
  9. Its a brand new battery so it can't be dead or dying

    Why not??. Have it tested.
  10. WRONG ASSUMPTION. Wrong because it's not yet proven. If the battery is not holding voltage, check the battery FIRST.

    Before you make any more assumptions, CHECK that the battery is NOT bad. Charge the battery fully, leave for 12 hours or so, and measure voltage.

    Batteries will lose charge progressively immediately AFTER any charging, until they reach what is known as "float voltage". Float voltage is what you are interested in here if you battery is flat.

    A nominal 12V battery is flat/stuffed if the float voltage is less than about 12.7-12.8V. Just because it is new does not guarantee that it is good. If cell levels are wrong, you have a problem. If acid SG is wrong you have a problem.

    Once you are satisfied that the battery is capable of holding charge, then look to see if you have a slow drain somewhere.

    One quick check for a slow drain is to add a 12V globe in series (between the negative terminal and the negative lead). It will illuminate when you turn the ignition or lights on, but if it is glowing when you have everything off you can see clearly that something is drawing current.
  11. Also, if it IS the negative lead, being a modern bike it will have a negative ground. This means that the negative terminal is earthed to the frame, motor, and just about every metal part on the bike.

    Whatever you are looking at (if it does link to the negative terminal) has nothing to do with your problem.
  12. Thank MacManMike. I will get the battery charged and checked.

    Then I'll try the light bulb trick.
  13. Was trying to think of a simple analogy and came up with this:

    If you have a bucket that doesn't hold water, even if it's a new one, you make sure it doesn't have a hole in it before you ring and hassle the Board of Works!

  14. ok so i charged it up ($10 battery chargers @ supercheap!!)

    Let it sit for 12 hours or so not hooked up to bike.


    Let it sit for a further 6 hours. 13.08V. Still not hooked up to bike.

    Hooked up to bike with everything connected.

    2-3 hours later. 13.05V.

    I've unplugged the reg/rec and I'll see if it goes down at all after that. I tested voltage after I unplugged it just in case and it was still 13.05V.

    Cross fingers it doesnt go down.
  15. went down to 13.02V overnight with the reg/rec unplugged.


    The regulator/Rectifier is too hot to touch before the bike is even at running temperature. Is this normal? Maybe 2 or 3 minutes of the bike running and its too hot to touch.

    If anyone else has a F series ZX6R could you check this for me?
  16. do u have any aftermarket electricals?

    i hade the same problem on my previous bike... it was cuz i had HID head lights put in ...110/90 instead of the 55/60 that is standard with the bike. high powered head lights DRAIN the battery like no tomorow.