Bring a large pot of lightly salted water to a boil. Add pasta and cook for 8 to 10 minutes or until al dente; drain.
In a large bowl combine oil, lime juice, chili powder, cumin, salt and garlic. Stir in pasta and set aside to cool to room temperature, stirring occasionally.
Stir in corn, beans, green pepper, red pepper and 1/2 of the cilantro leaves. Spoon onto a platter and garnish with tomatoes and remaining cilantro. Serve chilled or at room temperature.