For orange-chipotle mayonnaise:
Mix all ingredients in small bowl. Season to taste with salt and pepper.
For jerk sauce:
Finely chop first 4 ingredients in processor. Add sugar and next 4 ingredients; process until almost smooth. Season with salt and pepper.
Prepare barbecue (medium-high heat). Set aside 3/4 cup jerk sauce. Shape ground beef into six 1/2- to 3/4-inch-thick patties; place in 13x9x2-inch glass baking dish. Pour 1/2 cup jerk sauce over patties and turn to coat; let stand 20 minutes.
Sprinkle patties with salt and pepper. Grill to desired doneness, brushing occasionally with remaining jerk sauce, about 4 minutes per side for medium.
Spread mayonnaise over cut surfaces of buns. Place burgers on bottom halves of buns. Top with onion slices, tomato slices, lettuce, and bun tops. Serve, passing reserved 3/4 cup jerk sauce separately