Cook the pasta in a large saucepan of lightly salted boiling water for 10–12 minutes, or according to the packet instructions, until al dente. Drain the pasta and keep warm, reserving 120 ml of the cooking liquid.
Meanwhile, heat the oil in large frying pan over a moderate heat. Add the bacon and sauté for 4 minutes until just beginning to become crisp. Add the onion and garlic to the pan and cook for 5 minutes, stirring frequently, until the onion is tender. Add the capsicum and fennel and cook for 7 minutes until softened.
Stir the reserved pasta cooking liquid into the frying pan along with the tomatoes and orange juice. Season with salt and pepper, and bring to the boil. Reduce to a simmer, cover and cook for 5 minutes, or until the fennel is tender and the sauce is a good coating consistency.
Stir in the crabmeat and heat gently for 2–3 minutes until heated through. Transfer to a serving dish. Add the pasta, toss to combine and serve.