Bought a 96 Dolphin 535 last fall. Drove it from Flint, Michigan home to Terre Haute, IN ( about 550 miles).
Very sloppy steering and a vibration that started at 40, peaked at 48, and stopped completely at 55. Replaced the bell crank and had it aligned. Removed 6 double coin tires and installed Michelin XZEs, left double coins on the tag axle. Now it's down to more of a hum at the same speeds. You can feel it in the seat at it's peak. Any help would be appreciated.