Prepare the pasta according to the instructions on the packet. Then rinse and drain.
Mix the vinegar with salt, sugar and pepper. Gradually mix in the oil and water, mix the sauce with the pasta and let it steep for about 1 to 2 hours.
Rinse and dice the mozzarella, quarter the tomatoes, drain the corn. Cut the spring onions into rings and the radicchio into strips. Mix all ingredients with the pasta and season with salt and pepper.