Pull off the thin membrane from the underside of the rack of ribs. Blot each rack of ribs with a paper towel to dry. Rub the spice rub into the ribs on all sides.
Grill ribs, bone side down, over indirect heat with the grill lid closed 2 1/2 to 3 hours or until the meat just starts to shrink back from the ends of the bones. To ensure even cooking, place an oven thermometer next to the ribs (grill should be about 250°F).
Baste ribs with the Sticky Sweet Bar-B-Q Sauce every 10 minutes during the last 30 minutes of cooking. Remove from grill; slice and serve.