And the best replacement is still OEM Buell Y0302.5A8 (L19D)?
YES
Any better options out there?
not without a ridiculous amount of unnecessary work involved.
DAVID:
1-invest in a quality 12 volt charger with at least 6 amp steady-rate output capacity. the higher the better. a life-time investment and these lead-acid/AGM batteries suffer extensively when being brought back up to full steady-state static voltage with a POS tender.
2-you've been on here long enough to know the "check cables and battery fuse for corrosion" drill....but your stator is fine----your VR is on death-row.
13.5-14.7 volts DC at approx. 2500-3000rpm with no drop-outs or spikes is the proper range. doubt you have that.