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Discussion Starter #1
So I got my B3 back from the dealer last wednesday (sprag and coolant fixes) and I've ridden it basically every day since then. I went out on a ride today that lasted probably 100 miles. I stopped at the house of one of the guys I was riding with and when I came out to start the bike I turned the key on, all the lights came on, the fuel pump primed but when I went to start the bike everything went blank. I tried undoing the key and trying again and it wouldnt even turn the dash or lights on. Checked the fuses and all was well. Popped the tank off and the battery showed 11.5V which is a little low. Tried jumping the bike and while the dash and everything would turn on it wouldnt even try to turn over. Now lets assume that the battery is dead. There is clearly a problem that led to a bike having a dead battery after riding for 100 miles and sitting, with the key out, for maybe 20 minutes.
 

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I then imagine you're another one of a long list of guys who's "new" batteries are worthless. You can check your charging system also, but my money's on the battery.
 

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Discussion Starter #5
What confuses me though is the fact that 11.5V should be more than enough to power the lights on the dash. Nevertheless the dealer is coming to pick the bike up and I'll let them figure it out.
 

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Didn't have it turned to "park", that useless feature can suck the battery dead pretty quick.

Might be worth having the battery load tested before purchasing a new one.
 

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nneal12, listen to these good folks. Your battery is toast. My guess is that it is a stock Koyo P.O.S. and should be replaced. 11.5 volts will probably kick in an ECU protection scheme and nothing will work. It is certainly not enough voltage to turn a starter.
Don't cheap out on the new battery...buy a quality Yuasa ore equivalent with enough CCA to do the job.

FWIW, a new battery sitting on the shelf should generate 13.2 volts.
 

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You said you had the sprag issue. 5 bucks says you cooked the "crappy" Koyo trying to get it started when the sprag was giving you issues.
 

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Discussion Starter #11
I had the sprag issue 350 miles before the battery died. Correct me if I'm wrong but isn't the charging system supposed to charge the battery. I find it very very difficult to believe that the battery could lose so much capacitance that 350 miles of charging wasn't enough to keep the battery charged for 20 minutes of sitting.
 

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Discussion Starter #12
I completely agree that the battery is dead. I Dont agree that its just because it had a shitty battery. I'll probably just put a shorai in it. But I Dont want to drop 200 bucks on a new battery just to have that one get killed by the system.
 

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Unless you have a crap battery that was toast (after fighting with the sprag) to begin with.

I had to replace my trucks battery after 2 years of daily 100 mile (round trip) open freeway commuting.

If it cant hold charge, it cant hold charge.

Do you have an alarm fitted?
 

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Discussion Starter #14
No alarm. If it couldn't hold charge then it shouldn't have worked after sitting overnight every day of the week.
 

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nneal, if you would listen to my experience, and that of others, you might glean some useful information. Do you have the capability to measure the amperage drain (parasitic, or vampire, if you will) with the bike off and an ammeter hooked up to do the measurement? If you do, then get that measurement and you can back-calculate how long your battery should last from fully charged (13.2 vdc).

My experience with a brand new 2010 Brutale 1090RR was that the battery eventually could not hold a charge for several hours...let alone overnight. It simply quit working. Yes, it was a P.O.S. Koyo. This happened at Bub 4 with a lot of talent available to push start and trouble shoot and make recommendations. The fix: a new Yuasa battery. NO problems since whether or not I trickle charge the bike.

The battery went from working one day to not working the next. Overnight. Yes, it does happen...quite frequently with the Koyo unit that probably came with your bike.
 

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My Koyo was also garbage, but with regards to the "park" function (unless they changed it for the 3s, I doubt it) you have ON (full clockwise), OFF (one click counter), LOCK (another long turn counter), then P (another short click counter). The P leaves some lights on and kills a battery quick (I think Ducati also have this odd feature). 20min is more than enough to kill your battery, especially if it's already weak.
 

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My Koyo was also garbage, but with regards to the "park" function (unless they changed it for the 3s, I doubt it) you have ON (full clockwise), OFF (one click counter), LOCK (another long turn counter), then P (another short click counter). The P leaves some lights on and kills a battery quick (I think Ducati also have this odd feature). 20min is more than enough to kill your battery, especially if it's already weak.
You are correct with the Park function.
Only the B3 does not have this Park function.
Must have something to do with the small battery and this battery being so far far away underneath the gastank:)
 

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Discussion Starter #18
Do you have the capability to measure the amperage drain (parasitic, or vampire, if you will) with the bike off and an ammeter hooked up to do the measurement?
I think I have a multimeter lying around the garage somewhere. I'll try and find it tonight.

I want to apologize if I'm coming across as dismissing the idea that the battery is crap despite what everyone has said and experienced. I totally agree with everyone that the batteries which come with the bike are terrible. I just want to rule everything out so I dont spend money buying a nice battery only to have this same thing happen again.
 

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It's just a battery. Dump it. Get a new one. Make sure the new one is initiated correctly. Use a battery tender. Be without worries for the next several years. :smoking:
 
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