Ted, I think you kinda missed my point....I probably didn't make it very well.
Yes, a Battery Tender will charge up your new battery, but never up to max
capacity. Problem is, the Tender gets fooled into thinking Batt is at full charge and shuts down to a trickle charge. All step chargers will do this. So the cells never are fully up to max output....will discharge faster, won't deliver max voltage.

A new Batt that you've just added Acid to needs to be "cooked" just a bit to bring the cells up to max charge. Read the Yuasa instructions. They make this exact point.

No, you don't want to cook it over night on an 8 or 10 amp car battery charger, but a 4 to 6 hour stint on 2.5 or 3 amps is what is needed to kind of "kick Start" it. From there forward it should not be charged at that rate unless it's totally dead, and then only for a short time. The "smart" chargers are the ticket but they don't work well for intial charge.

I have three or four, a couple for my sound gear and a couple more for the bikes. My entire sound cart (totally portable digital sound recording set up for
doing "film/video production sound".

All runs on DC ...3 big 20 AH batts run wireless receivers, mixing board, Comtec system, my Gerbing jacket (for night work), scanners, digi video recorder (for playback), speakers, power conditioners, digital sound recorders (two), analog recorder (one), and a bunch of other crap. I have two on board chargers that I plug in when ever possible. Otherwise its an ALL DC operation. No humms, buzzes EMI or RFI. I can go about 12 hours using only my own batteries. If my batteries fail I am ....screwed.....

Patrick

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Patrick passed Dec 2018. RIP Patrick!

Yer, Ill go along with that !

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Did some trips.
Rode some bikes.
Fix them for a living.
Can't say anymore.