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How Long Do You Trust An Older Battery, Even If It Tests Good?

Dr. Dolittle

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My bike is almost exactly 4 years old so the battery is at least that old if not a bit older, allowing for time sitting on the showroom floor. It's always parked in a garage and left on a Battery Tender Junior.

Ran some of the tests from the Self Help Section and got these results:

1. Under no load, the battery reads a steady 12.8 volts
2. After 10 seconds on a 100 amp load tester, the battery read 10.2 volts
3. Pulled the fuel pump fuse and after 5 seconds of starter engagement, the battery read 10.4 volts

I've read that properly maintained batteries are usually good for 3-5 years so I'm right in the middle of that range. It seems to be testing out OK so I'm inclined to keep it.

Any thoughts?
 
Dr, My 07 Bob battery went down a couple weeks ago with no warning, it gets ridden every day so I do not like surprises, If you have any doubts I would replace it for peace of mind and it will be easier on your electrical system trying to play catch up dont forget to check the charge on a new battery @ 12,7 volts:s
 
I have replaced 1 battery it my last bike that I owned for 10 years. So in my opinion I would just keep on keeping on for your battery checks out ok. In my experience though with proper maintance when a battery would fail I had no warning but they always seem to quit when I tryed to go for a ride from the house and never out on the road........:s
 
Dr, My 07 Bob battery went down a couple weeks ago with no warning, it gets ridden every day so I do not like surprises, If you have any doubts I would replace it for peace of mind and it will be easier on your electrical system trying to play catch up dont forget to check the charge on a new battery @ 12,7 volts:s

Thanks, Jack.

This time of year I'm lucky to get out once a week for a couple hours. Before any overnight trip in the future, I'll probably get a new one to avoid any surprises like you had!

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they always seem to quit when I tryed to go for a ride from the house and never out on the road........:s

That's kind of what I'm counting on. At least all you lose is a day's ride and your not stranded somewhere.
 
I don't have much trust in a battery that is more than about 4 years old. The life span of a battery is on average 4 years give or take. I'd rather replace it at 4 years old than get stuck at a bad time on the road.
 
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My '07 still has the factory battery in it. I did the load test in Aug. and it was close to Dr. D's numbers. I am going to put a new Deka in it before my 2 wk. road trip in May. After reading Capitol Jack's reply, maybe sooner.
My buddy's '07 battery died last spring.
 
After 4 years i'd be getting ready for a new one.
And if you do get a new battery, Before you put it in the bike, FULLY charge it yourself, Don't let some battery salesman tell you it's good to go off the shelf.
 
After 10 seconds on a 100 amp load tester, the battery read 10.2 volts
Any thoughts?

On a fully charged battery, 100 amps for 10 seconds @ 10.40 volts is weak. Without even trying it, I can tell you it won't pass 50% of its CCA for 15 seconds.
The CCA has to be somewhere around 280, maybe even 300. A number that the Moco supplied, not one we made up. So 150 for 15 seconds @ 9.8 would be just passing. Plus think of the extra labor that is being placed on your stator & regulator...
I would change it.
 
On a fully charged battery, 100 amps for 10 seconds @ 10.40 volts is weak. Without even trying it, I can tell you it won't pass 50% of its CCA for 15 seconds.
The CCA has to be somewhere around 280, maybe even 300. A number that the Moco supplied, not one we made up. So 150 for 15 seconds @ 9.8 would be just passing. Plus think of the extra labor that is being placed on your stator & regulator...
I would change it.

Leave it to Hoople to put it in terms I can understand.:cheers
 
With the old stator and rotor and regulator at idle with brake lights and driving lights on the volt meter would show 11 volts or less. My volt meter reads low, maximum volts showing would be less then 14 volts. This is the way it has been for 6 years that I have owned the bike. Now idling with everything on the volt meter hardly moves down and max volts is still just below the 14 volt.
Ken
 
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