Tidings, what was the first year that the Motor Company "rubber mounted" the engine on the Sportster? Secondly, did this make a major difference in vibration? Please respond.
As Hobbit says, 2004 model year. You can see the "Dog Bone" links 2 in front, one in underside near the swing arm; the big rubber isolators (the rubber donut 'bout the size of your palm front and rear of base of engine nested in frame and swingarm).