Does one drain flat kill a AGM?
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From: Beyond Fucital
When I was laid up in the hospital, my truck battery drained dead, wouldn't even jump, it's 6 years old so I figured it's due to replace.
I put a charger on it to get it up enough for a tender and it took the charge. Been starting good for the past 2 weeks now that I'm back to work using it.
I put a charger on it to get it up enough for a tender and it took the charge. Been starting good for the past 2 weeks now that I'm back to work using it.
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From: SWFL
When any battery gets very low it needs a fast charge or higher amp to get the "juices" flowing. A multiple amp charger is needed for that. Once the needle starts moving up charger can be switched to lower amp. Then down to lowest setting for a low slow charge. Your welcome.
Im just fooling with you. Ill see what I get tomorrow morning. If it starts, Ill let the stator dump 20 or so amps into it quick enough. That should get the juices flowing and the needle moving ;-)
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Joined: Jan 2009
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From: WACO
I purchased a $80.00 Schumacher digital charger. It crapped out within a year. I am now using a Harbor Freight "analog" ?charger. I have always had several cars, trucks ,motorcycles so I have always needed a charger. They just do not make them like they used to. All chinese crap.
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Club Member
Joined: Dec 2014
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From: SWFL
I purchased a $80.00 Schumacher digital charger. It crapped out within a year. I am now using a Harbor Freight "analog" ?charger. I have always had several cars, trucks ,motorcycles so I have always needed a charger. They just do not make them like they used to. All chinese crap.
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Joined: Sep 2017
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From: England
Some chargers like the optimate have a specific mode to get flat batteries going again.
I think for most motorcycle batteries 5 amps might be too high. I have seen other chargers that has a car and bike mode and the difference is to lower the charge amperage.
Yuasa only recommends 3 amps for their batteries - Motorcyle battery charging and discharging information guide (yuasa.co.uk)
I think for most motorcycle batteries 5 amps might be too high. I have seen other chargers that has a car and bike mode and the difference is to lower the charge amperage.
Yuasa only recommends 3 amps for their batteries - Motorcyle battery charging and discharging information guide (yuasa.co.uk)
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Joined: Mar 2008
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From: bklyn,ny
Some chargers like the optimate have a specific mode to get flat batteries going again.
I think for most motorcycle batteries 5 amps might be too high. I have seen other chargers that has a car and bike mode and the difference is to lower the charge amperage.
Yuasa only recommends 3 amps for their batteries - Motorcyle battery charging and discharging information guide (yuasa.co.uk)
I think for most motorcycle batteries 5 amps might be too high. I have seen other chargers that has a car and bike mode and the difference is to lower the charge amperage.
Yuasa only recommends 3 amps for their batteries - Motorcyle battery charging and discharging information guide (yuasa.co.uk)
Seasoned HDF Member
Joined: Sep 2017
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From: England
The text from Yuasa states 3 Amps, "When charging a motorcycle or other small battery, the battery charger should not exceed 3 amps."
Yes the Optimate can charge at 5 amps. I didn't dispute that I just used the information from Yuasa to state that might be too high. It also states it has Ampmatic control to reduce charging current for small batteries which I have just noticed.
Yes the Optimate can charge at 5 amps. I didn't dispute that I just used the information from Yuasa to state that might be too high. It also states it has Ampmatic control to reduce charging current for small batteries which I have just noticed.
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Joined: Dec 2017
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From: Plover, WI
The text from Yuasa states 3 Amps, "When charging a motorcycle or other small battery, the battery charger should not exceed 3 amps."
Yes the Optimate can charge at 5 amps. I didn't dispute that I just used the information from Yuasa to state that might be too high. It also states it has Ampmatic control to reduce charging current for small batteries which I have just noticed.
Yes the Optimate can charge at 5 amps. I didn't dispute that I just used the information from Yuasa to state that might be too high. It also states it has Ampmatic control to reduce charging current for small batteries which I have just noticed.
Seems to coincide with the charge rate displayed on their latest and greatest.
Last edited by barneyboy; Dec 13, 2021 at 04:22 PM.
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From: New York
If you can get the battery recharged, I don't think you are going to experience problems on the front end - it's the back-end where problems will develop. Expect increasing hesitation when kicking over the bike and a shortened life span. The threshold for an AGM is about 50% of "state of charge". That's one of the bonuses for Lithium batteries - they can be discharged almost to 0 state of charge without shortening their useful life.