Davidson, “ST” usually stands for Softail, but in newer models, it can also mean Sport Touring, depending on the lineup.
The old adage of "Old Harleys leak" isn't indicative of reliability issues. Rather, it can signal the model year and ...
Harley-Davidson model codes can be confusing, with a combination of four or five letters signifying various aspects of a bike. FLFB is just one example.