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Will an amp kill a battery in 10 minutes???

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Old Aug 25, 2010 | 04:40 PM
  #1  
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Default Will an amp kill a battery in 10 minutes???

I just installed the J & M amp and speakers last Sunday, and I rode it home from my Dad's which took me about an hour, and I was listening to the stereo on the way home. I haven't had a chance to ride since then, but I've gone out to the shop to listen to the stereo a few times for a couple of minutes (just for grins) with the bike turned off. I went out today to take a ride and the battery was completely dead. I've got it connected to the battery tender right now, hoping it will hold a charge and that it's not ruined. Could have listening to the stereo for a combined 10-15 minutes with the bike off possibly kill my battery that quickly?? It's just strange because when I turned the bike off after listening to it it seemed fine and now today there wasn't even enough juice to turn on the headlight or prime the fuel pump, which seems very odd to me. Could I have possibly installed the amp incorrectly that would be creating a constant drain on the battery? The battery's only two years old and has never gone dead on me before.

Thanks in advance for whatever help you can give me, Jeff.
 

Last edited by jeff.georgalas; Aug 25, 2010 at 04:44 PM. Reason: Omitted something
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Old Aug 25, 2010 | 06:57 PM
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All power amplifiers draw serious current. Depending on the condition of your charging system and the state of your battery....yes, it would drain the battery given enough time.

P (power in watts) = I (current in amps) x E (voltage). Manipulate this formula and it becomes I=P/E. In this case I=250/12 (nominal battery voltage) or 20.333 plus amps.
 
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Old Aug 26, 2010 | 06:29 AM
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Originally Posted by jeff.georgalas
I just installed the J & M amp and speakers last Sunday, and I rode it home from my Dad's which took me about an hour, and I was listening to the stereo on the way home. I haven't had a chance to ride since then, but I've gone out to the shop to listen to the stereo a few times for a couple of minutes (just for grins) with the bike turned off. I went out today to take a ride and the battery was completely dead. I've got it connected to the battery tender right now, hoping it will hold a charge and that it's not ruined. Could have listening to the stereo for a combined 10-15 minutes with the bike off possibly kill my battery that quickly?? It's just strange because when I turned the bike off after listening to it it seemed fine and now today there wasn't even enough juice to turn on the headlight or prime the fuel pump, which seems very odd to me. Could I have possibly installed the amp incorrectly that would be creating a constant drain on the battery? The battery's only two years old and has never gone dead on me before.

Thanks in advance for whatever help you can give me, Jeff.
BTW, be aware that if your battery is "too dead" then the battery tender wont bring it back up. You will need to use a regular charger.
 
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Old Aug 26, 2010 | 06:34 AM
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I dont think that amp should kill the battery in that time.
I would check for something drawing current when the bike is off,check battery condition,etc-.
 
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Old Aug 26, 2010 | 07:09 PM
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Are your sure that the amp is turned off and not on all the time I have the same or similar system and I have the amp on a toggle so I can make sure it's dead when not running That amp is probably 40 plus watts and will kill a bat (bike not running ) say 4+ hours
 
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