In a skillet, cook the chopped bacon over medium heat until browned. Use a slotted spoon to transfer the bacon to a plate lined with paper towels.
In a separate dry skillet over medium heat, toast the pine nuts until they are golden and fragrant, stirring frequently for about 3 minutes. Transfer them to a plate and set aside.
In a large mixing bowl, combine the broccoli florets, cucumber slices, halved grapes, diced red onion, browned bacon, and toasted pine nuts.
In a smaller bowl, whisk together the mayonnaise, lemon juice, sugar, salt, and pepper until smooth.
Pour the dressing over the salad and toss gently to coat all ingredients. Serve immediately or refrigerate until ready to enjoy.