My last motorcycle was a 2002 HD Dyna SuperGlide, which I gave up when my lower back, hips, knees, shoulders, and neck told me I would spend several days in pain for every hour of riding.
Prior to that I had a 1996 HD 1200 XLCH Sportster (full Screaming Eagle treatment). Great for scooting around town, but not so good on extended road trips.
Others through the years have included a 1976 HD Sportster, 1965 Norton Commando, and a few lesser beasts. Had some time on the police motorcycles during the 1970s including full-dress Harleys and the Kawasaki 900 and 1000 series.
I always enjoyed riding, but it finally came down to a contest between old injuries and arthritis vs. a little temporary pleasure as a prelude to days of discomfort.
Life is good, except for the getting old part.