As mentioned above if the jets are warn oval they are useless and you'll be wasting any time spent trying to set the carbs up. I had a similar poor running problem on my little 600SS - I did the full monty, set up the float heights properly (check out that ducati suite site), replaced the jets, fitted a S2 kit, synced them and did the valves too. Hey presto she ran like dream and still is a festy little bike for a 583cc job.