Cook the pasta in a large saucepan of salted, boiling water for 8-10 minutes until 'al dente.'
Meanwhile, season the smoked salmon with the lemon juice and some black pepper. Drain the pasta and run under cold water until cold.
Toss with the beetroot salad in a large mixing bowl. Spoon into glass serving bowls and garnish with the smoked salmon and some more black pepper before serving.