Charging System Failure Modes

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I got the new battery today. I "activated" it by adding the acid and am currently (pun) giving it a slow charge at ~1 amp. I know that the batteries are "dry charged" but still need topping off. Probably won't get around to proper testing for a few days. (work tomorrow and heavy rain forecast for the weekend) I'll see how the new battery works out and quite possibly get the harness ordered.

Interesting observation Brodie made with respect to oxidation of the surface of the copper wires.

 
The current between the R/R and battery should typically be small. On my non-abs '04 the only current in that loop is the battery charging current (< 2 amps) and the fuel pump & injectors (7+ amps).

Of course if you connect a bunch of accessory loads to the battery terminals that current must also flow from the R/R to the battery terminals.

So, the add-on accessory loads may max-out or overload the capacity of that loop.

They should have included a tapping terminal for accessory loads near the R/R. All power originates there so accessory loads should be sourced nearby.

I assumed the black and red conductors at the battery were a bit larger than 12 awg. They appear to be larger although I don't know the thickness of the insulation. When a circuit is quite short it may be assumed that some of the heat will be wicked from the conductors to the end devices which will absorb heat.

 
I got the new battery today. I "activated" it by adding the acid and am currently (pun) giving it a slow charge at ~1 amp. I know that the batteries are "dry charged" but still need topping off. Probably won't get around to proper testing for a few days. ...
Whatever you do, don't leaving it charging at ~1 amp for more than a couple of hours or your new battery may be worse than your old one. If you are using a trickle charger, stop it (and disconnect it from the battery). Only a good battery tender is relatively safe to leave on, but for my money, I wouldn't leave it connected any more than is strictly necessary.
This from someone who doesn't own a battery charger of any kind, and hasn't bought a replacement battery in any vehicle since I recovered a wrecked MGB GT about 43 years ago, though it has to be said my vehicle batteries tend to have a relatively benign environment.

[edit]On reflection, I didn't even replace the MG's batteries, it had been kindly left upside-down by the previous owner, so the batteries were drained of acid and had therefore been stored dry charged for the year or so it sat in a breaker's yard, I simply put acid in them :) .[/edit]

 
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I got the new battery today. I "activated" it by adding the acid and am currently (pun) giving it a slow charge at ~1 amp. I know that the batteries are "dry charged" but still need topping off. Probably won't get around to proper testing for a few days. ...
Whatever you do, don't leaving it charging at ~1 amp for more than a couple of hours or your new battery may be worse than your old one. If you are using a trickle charger, stop it (and disconnect it from the battery). Only a good battery tender is relatively safe to leave on, but for my money, I wouldn't leave it connected any more than is strictly necessary.
I understand lead acid battery chemistry/physics quite well. The slow charge (@ 750 milliamp)is just to bring it up to within 90% of "full". It is better to do that slowly under controlled conditions than to put a half-charged battery into the bike and let the charging system dump in as high a current as it can. I monitor voltage regularly and disconnect before I hit the recommended "float" voltage for this type of battery (~13.6V at room temperature, depending on what reference you read). (I actually took it off around 13.4V, let it "rest" to dissipate surface charge and took it to 13.4V again) Both overcharging and discharging to below 50% of capacity are bad for AGM batteries.

I realize that I wasn't very specific about my "topping off" procedure and it is important to avoid overcharging or charging at too high a rate. Ideally, one should charge at less than C/10 or one tenth the ampere-hour rating (capacity) of the battery - 1.2 amp rate for a 12 ampere-hour battery like the Yuasa YT14B-BS I bought. Within reason, the AGM will tolerate a faster rate but slower is better. Many unregulated car battery chargers will hit a discharged powersport battery with 5-10 amps which is WAY too much.

 
Only a good battery tender is relatively safe to leave on, but for my money, I wouldn't leave it connected any more than is strictly necessary.
Deltran explains itself and shows it's work in its documentation that then concludes about 48 hours for an initial charge. I only know this because I was looking at its docs after buying a new battery 2 weeks ago. I always have done at least an overnight or 24 hours as a rule of thumb so its 48 hour conclusion stood out.

It's dependent on the amp-hour rating of the battery.

Can the Battery Tender Plus successfully perform the initial charge on a new, flooded, motorcycle battery?Background: The motorcycle dealers receive batteries from the manufacturer in a dry state. The plates are dried out, and there is no acid in the cell compartments. (Do not confuse this with a dry-cell battery.) The dealer must fill the individual battery cells with acid and then put them on a shop charger to pre-charge prior to selling them to a customer. As the batteries arrive from the manufacturer, the plates are approximately 80% "formed". The initial pre-charge, post-formation charge, or more correctly, formation-finishing charge, must be conducted at a specific power level and for a specific time period. Each manufacturer has its own recommendations, for example one manufacturer recommends that the charger deliver a constant current equal to 10% to 15% of the battery amp-hour capacity and that the charge current be applied to the battery for a period of 5 to 10 hours.

Answer 1) Certainly if the dealer has properly pre-charged the battery after filling it with acid, then the answer is ABSOLUTELY YES.

Answer 2) If the dealer has not properly pre-charged the

newly filled battery prior to the sale, then the answer is YES, WITH SOME QUALIFICATIONS:

Qualification A) The Battery Tender® Plus should be left on the new battery for a minimum of 24 hours on float, in addition to whatever amount of time it takes for the charger to get to the float stage. It is not clear how to correlate the 80% formed plates with a given state of charge once the cells are filled with acid. To be safe, assume that the batteries require a full 100% charge after the cells are filled.

For example, a 16 Ah battery will take about 13 hours to get to the absorption voltage (constant 14.4 Volts). It may take another 6 to 8 hours to reach the float voltage (constant 13.2 Volts). This may sound awkward; because what happens is that the battery charge current drops while the absorption voltage is held constant. When the battery current drops to 0.1 amp, or if 6 to hours have elapsed at the absorption voltage, the charger automatically switches its output from 14.4 V to 13.2 V. So it may take the better part of 20 hours to reach the float stage. Add another 24 hours to that and you are at 44 hours. Throw in another 4 hours for good measure and you get a nice round, even 48 hours, or 2 days.

Qualification B ) Although there are probably several charging methods that will be equally effective, regardless of who manufactures the battery, in the interests of technical consistency, they will not officially sanction any initial charging method other than those published in their technical applications literature.
 
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