Around 0.8-1A is the usual recommended charge for these smaller batteries.
Good idea to have a charger for motorcycle batteries.
My charger has different modes. Motorcycle 0.8A, Car (max 5A), Car outside charging when cold (higher voltage)/AGM, Recond.
A good charger is not expensive. An investment for many years to come. Bought mine over 10 years ago.
I'll charge my motorcycle batteries ca 12-24 hours or until green LED on charger once a month or more in the season, ca 24 hours every 2nd month when parked.
Slow going long rides , less than 4000, maybe max 3500 rpm with heavy use of blinkers, brake lamp can drain battery.
Charge battery after a carb sync too
My car with 77Ah battery get a 48 hours charge now and then. Max current 5A.