Cook pasta according to package directions, omitting salt and fat. Drain and rinse with cold water. Drain; set aside.
Heat oil in a large nonstick skillet over medium-high heat. Add garlic; sauté 1 minute. Add turkey; cook until browned, stirring to crumble. Stir in water and taco seasoning; bring to a boil. Reduce heat, and simmer 4 minutes or until liquid almost evaporates and the turkey is done, stirring frequently. Remove from heat; cool slightly.
Combine pasta, turkey mixture, reduced-fat cheese, and next 6 ingredients (through beans) in a large bowl.
Combine lime juice, salt, cumin, and sour cream, stirring until well blended. Pour over pasta mixture; toss gently to coat. Serve with salsa, if desired.