Current bikes 2016 KTM 500 EXC, 2016 Yamaha TW 200
Battery Tender and Battery Tender Jr. charger for me in my '99. They told me the batteries are sent "not" fully charged after I ruined two of them. They replaced them for me free, but I had to pay shipping to them. Yikes! They told me if I discharged them too much, they would never re-charge. So far, I love my BT battery.
Tom in Wichita
78 Moto Guzzi SP1000
87 Yamaha TW200
99 Yamaha TW200
03 Honda Shadow Spirit (girlfriend's ride)
74 Moto Guzzi Eldorado Police model (in many pieces)
I used the Scorpian AGM battery. It is smaller than stock but turns over much better. About 6 months old, no issues regular battery charger.