In a bowl, combine the olive oil, orange juice, lemon juice, lime juice, salt, pepper and garlic cloves. Whisk together.
Place the chicken legs, juiced pieces of fruit and quartered onions in large plastic bags or a bowl. Pour the marinade over the top, tossing to combine. Cover with plastic wrap (if using bowl) or seal the bag up and marinate for at least 2 hours ... several hours is better. Toss a few times during the marinating process.
Preheat a grill. Grill the chicken legs until cooked all the way through, turning occasionally so the chicken is cooked on all sides, 10 to 12 minutes.
Separate the tortillas into 2 piles of 16, and then wrap each pile in foil and warm over the grill for 10 to 15 minutes.
Serve the chicken legs with the warm tortillas, pico de gallo, refried beans and chipotle salsa.