Preheat an outdoor grill for medium heat, and lightly oil the grate.
Cook potatoes on High heat in a microwave oven until softened slightly, about 10 minutes. Cut potatoes lengthwise into 1/2-inch thick sticks.
Combine salt, cumin, paprika, cinnamon, chipotle powder, vinegar, and olive oil in a large container with a tight-fitting lid. Place sweet potatoes in spice mixture; cover and shake gently until well coated.
Grill over low to medium heat, turning often and basting with any leftover sauce. Cook until sweet potatoes are fork-tender, 10 to 15 minutes.