Could it be one that I use quite often? :-k
Ignorance is bliss, and
boy, am I happy.
Well, he knows he is starting with a weak battery. What he might not realize is that he might be killing what's left of it by using a "trickle charger". :-k
If it is a MANUAL "trickle charger", it will sit there and slowly cook that battery with 1-2 amps the entire time it is connected. It will not taper off as it reaches full charge.
Even if it's an AUTOMATIC "trickle charger", it can still cook the battery, but it will take longer. It may start at 1-2 amps and taper off to less than 1/2 amp, but it's still too much for a constant charge.
It is better to use a battery MAINTAINER that will actually turn off the charge and monitor voltage, coming back on when needed. "Battery Tender" is one brand name, but somewhat expensive. Schumacher makes one that is available at Wal-Mart for about $20. If you are one who will avoid Wal-Mart, you can get the same exact unit, wearing a Die Hard label at Sears for about $30.
By the way, Killer, one reason to test the system at 5,000 rpm is because the charging characteristics are a bit different at that speed. A bike can charge PERFECTLY at 2-3k. In fact, that is about where it starts regulating. Turning the engine faster, it will start regulating more and more, ending up in saturation. THAT is where you want to do your testing.
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