Paul used to ride his Honda motorcycle from Queens to Manhattan on his way to school. At the time, the surface of the road on the bridge was under repair, and was grooved. This makes it feel "mushy" to ride a motorcycle on, I know from experience. "Feelin' Groovy" is simply the feeling he got from his bike on the grooves, with the double meaning that life is just a lot more "groovy" when experienced from a moving motorcycle. Paul Simon has told this story several times.
Paul used to ride his Honda motorcycle from Queens to Manhattan on his way to school. At the time, the surface of the road on the bridge was under repair, and was grooved. This makes it feel "mushy" to ride a motorcycle on, I know from experience. "Feelin' Groovy" is simply the feeling he got from his bike on the grooves, with the double meaning that life is just a lot more "groovy" when experienced from a moving motorcycle. Paul Simon has told this story several times.