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Battery drain---Bad!!!

O

olddude73

Guest
90K100LT. A new (2nd one) sealed battery (Wesco) drains down to below cranking power within 3 weeks. New, hot (14.2V) battery installed 3 weeks ago, and today was too low to crank engine. This is the 2nd time this has happened. First one caused me to fry the starter relay; costing me another $65.00.

Where & how should I look to find the problem???
 
gadwal said:
90K100LT. A new (2nd one) sealed battery (Wesco) drains down to below cranking power within 3 weeks. New, hot (14.2V) battery installed 3 weeks ago, and today was too low to crank engine. This is the 2nd time this has happened. First one caused me to fry the starter relay; costing me another $65.00.

Where & how should I look to find the problem???
Click to expand...

Gad,
Do you have a voltmeter with an amperage function? If so, put the ammeter between the disconnected ground cable and the battery. Do NOT turn the ignition on or try to start the bike or you will fry the meter. You should see somewhere around 2.1ma or less on the meter with the key in the OFF or locked position.

Let us know what you find.
 
Last edited:
Battery Drain

bmwmick said:
Gad,
Do you have a voltmeter with an amperage function? If so, put the ammeter between the disconnected ground cable and the battery. Do NOT turn the ignition on or try to start the bike or you will fry the meter. You should see somewhere around 21ma or less on the meter with the key in the OFF or locked position.

Let us know what you find.
Click to expand...

21 ma drain will drain 10,584 ma or 10.54 amps in a 3 week span. This is not a problem on a car battery, but with a 18 or 20 amp hour battery, half is gone. A car battery 10% or less.

That's why so many motorcyclist use a battery tender.

Ralph Sims
 
BuddingGeezer said:
21 ma drain will drain 10,584 ma or 10.54 amps in a 3 week span. This is not a problem on a car battery, but with a 18 or 20 amp hour battery, half is gone. A car battery 10% or less.

That's why so many motorcyclist use a battery tender.

Ralph Sims
Click to expand...

Ralph,
Thanks! I forgot the decimal point. I was wondering where you got that 21ma figure so I went back and read my post. I meant to type 2.1 :banghead :banghead :banghead
 
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