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'87 K75s Dead Battery Or?

kentuvman

New member
Hi Gang,

Have not had the K75s out since May - went to put on battery tender this morning and normally the red light comes on before I connect to power - this time it did not - turned ignition switch and dead - no power.

Connected 12V battery charger on positive terminal by taking off one side cover and grounded to frame. Battery almost indicates charged - turned on key and the tach rocketed up - strange. Clock did come on as did the other normal indicator lights when switched on. Was also on the 2 amp slow charge setting on charger.

Put a voltmeter to + terminal and grounded other side to frame & getting less than 1.5 volts.

Battery on bike is a Westco sealed 12V20P
Bought @ March 2010.

Normally when charger connected, I hear the humming from the charger - I'm hearing a slight humming noise somewhere near the battery on the bike.

So, right now in PAUSE mode - charger not connected to bike.

Guessing bad battery but wondering why tach needle shot up when I turned on ignition switch with battery charger on the lowest setting.

Thanks for your help in advance & Happy & Safe July 4th weekend holiday!
:usa
 
Put voltmeter directly on both battery terminals (not on the wires or bolts connected to terminals). If you still get 1.5 volts, the battery is the problem. If you get much higher, the connections are the problem.

Most battery chargers will not show charging when first connected to a battery that is completely discharged. Some times it will take many hours at around 10 amps to even start showing a charge on the charger's meter.

If the voltmeter shows that the battery is the problem, I would remove the battery before trying to charge it. Batteries can have a nasty tendency to do bad things (like explode) when something is internally wrong and high current is being applied to them. Better safe than sorry.



:dance:dance:dance
 
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Put voltmeter directly on both battery terminals (not on the wires or bolts connected to terminals). If you still get 1.5 volts, the battery is the problem. If you get much higher, the connections are the problem.

Most battery chargers will not show charging when first connected to a battery that is completely discharged. Some times it will take many hours at around 10 amps to even start showing a charge on the chargers meter.

If the voltmeter shows that the battery is the problem, I would remove the battery before trying to charge it. Batteries can have a nasty tendency to do bad things (like explode) when something is internally wrong and high current is being applied to them. Better safe than sorry.



:dance:dance:dance

Thanks, Lee - did remove both side covers - current is 1.5 - will replace!!! (cheap insurance)
 
I had similiar problem

I had similar problem on my old k75s (smoothest bike I ever owned) and if tapped on top on the starter relay (under the seat), it would fix the problem. Easy and inexpensive thing to try.

DW
 
I replaced the battery with a comparable battery from Fleet Farm - and I'm good.

The Westco I replaced surprised me. It was dead as a doornail and wouldn't take a charge. I've heard of sealed batteries going quick but now I've seen it with my own eyes.
 
You're right

If your starter relay was sticking it was probably because your battery was low. You temporarily fixed a symptom, not the problem.

As I can faintly remember, I did change that old battery out shortly after that episode. But, I well remember that when it happened I was about 3000 miles away from home in a little town on hwy 191 between Yellow Stone and Four Corners, Montana. And, when I beat on the top of that relay, it sure fixed my problem at the time.

DW
 
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