Slice cucumbers into thin rounds or half-moons. Place in a colander, toss with 1 teaspoon salt, and let sit for 20 minutes to draw out excess water. Rinse under cold water and pat dry with paper towels.
While cucumbers rest, slice bell peppers into thin strips and red onion into thin rings. Set aside.
In a small bowl, whisk together rice vinegar, olive oil, honey, 1 teaspoon salt, black pepper, and red pepper flakes until honey is dissolved.
In a large bowl, combine cucumbers, bell peppers, red onion, and fresh dill. Pour dressing over the vegetables and toss well to coat.
Let the salad sit at room temperature for 10 minutes before serving to allow flavors to meld. Serve chilled or at room temperature.