Place each ear of corn on a sheet of aluminum foil large enough to wrap it completely; brush with butter. Season with salt.
Spread brown sugar evenly on a large plate. Roll buttered corn in brown sugar.
Wrap 2 bacon slices around the length of each ear of corn. Wrap foil around corn, enclosing it completely.
Preheat grill for medium heat and lightly oil the grate. Cook foil-wrapped corn over indirect heat, turning occasionally, until corn is tender and bacon is crisp, 35 to 45 minutes.