In a small bowl combine sugar, seasoning, paprika, chile pepper, and black pepper. Remove and reserve 1 teaspoon spice mixture. Add remaining spice mixture to a large resealable plastic bag. Add chicken to bag and toss to coat.
For a charcoal grill, grill chicken on rack of an uncovered grill directly over medium coals for 12 to 15 minutes or until chicken is no longer pink (170 degrees F), turning once halfway through grilling. (For a gas grill, preheat grill. Reduce heat to medium. Cover and grill as above.) Wrap tortillas tightly in heavy foil. Add to grill the last 10 minutes of grilling time, turning once halfway through grilling. Remove chicken from grill and thinly slice.
Meanwhile, in a small bowl combine reserved spice mixture, yogurt, mayonnaise, vinegar, and syrup. Spread mixture evenly over one side of each tortilla. Top with lettuce, cheese, and sliced chicken. Roll up into wraps. Makes 6 servings.