Preheat oven to 450 degrees F. Halve all seven clementines. Thinly slice four halves into half-moons; set all aside.
Rinse chicken body cavity; pat dry. Season inside and outside of chicken with salt and black pepper. Place one clementine half in cavity. Twist wing tips under back; tie drumsticks together using 100-percent- cotton kitchen string. Place breast side up in a 1392-inch baking pan or dish.
Lay bacon lengthwise on chicken breast; tuck six sage leaves and all clementine slices under bacon.
For vinaigrette: Over a small bowl juice four clementine halves. Whisk in maple syrup, sherry, oil, and garlic; set aside.
Place remaining five clementine halves around chicken. Chop remaining sage leaves; sprinkle over clementines. Roast chicken 20 minutes. Spoon half the vinaigrette over chicken. Reduce heat to 350 degrees F; cover chicken with foil. Roast 50 to 60 minutes, spooning remaining vinaigrette over chicken every 15 minutes. Remove; set aside foil. Roast 10 minutes more or until a meat thermometer inserted into thigh registers at least 170 degrees F. Cover with foil; let stand 10 minutes. To serve, squeeze one roasted clementine half over chicken.