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Discussion Starter #1
Hello people!
My bike is a 2012 Classic and since I took it back to use after the winter the engine start is more laboured. I had the battery plugged to a tender a few times during the winter, but it seems that the battery has lost some power. Because the battery is relatively new, I want to be sure it is the problem.
So, those of you that have changed to a new battery. Did you notice and improvement in the starter motor power after changing to a new battery?
If so, I'm getting a new battery and a better tender.
 

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You really need to check the specific gravity and open circuit voltage to determine whether battery replacement is necesary. A 2012 battery should still have some life in it.
Open circuit voltage @
100% charge: 12.60Volts Relative acid Density: 1.265 grams/cubic centimeter
75% charge : 12.35 V Relative acid Density: 1.225 g/cc
50% charge : 12.10 V Relative acid Density: 1.190 g/cc
25% charge: 11.95 V Relative acid Density: 1.155 g/cc
0% : 11.7 V Rel. acid Density: 1.120 g/cc
These figures are just rough gudelines.
Battery type and construction, temperature, and any loads connected will vary.
 

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Next is battery voltage and Load.

While cranking the engine, the voltage should not drop below 9.6 volts at th terminals.

Once the engine starts and has been running the charging voltage should be just over 14 volts with a maximum of 14.7 volts.

You probably need a new battery. It should be under warranty.

David
 

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what he ^^^^ said.

Starter issues could be a bad connection--maybe some corrosion at contacts.

Or, unlikely, drying out of the grease in the starter.

But agree that a trip to the dealer is in the cards, for warranty, if not diagnosis.
 

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Discussion Starter #5
Ok. I´we done some measurements over the weekend.

Right after riding the battery has 12.91v
24h later is shows 12.71v
48h later 12.68v

When the engine is running the voltage is 14.2v

To me it seems the battery is ok. Next step is to check that the starter motor leads are not loose. After that... Dunno :icon_scratch:
 
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