Winter Fully charge, then disconnect or put battery minder/tender (Two different brands of same type of product) on it.
Summer, Check fluid level every month, top off with DISTILLED water if needed.
Proper level is between top of plates and 1/8" below bottom of filler tube.
NOTE: this assumes they are not "Maintenance Free" batteries.
Clean terminals annually.
Home was where I park it. but alas the.
2005 Damon Intruder 377 Alas declared a total loss
after a semi "nicked" it. Still have the radios
Kenwood TS-2000, ICOM ID-5100, ID-51A+2, ID-880 REF030C most times