Motorcycle Repair: 1979 suzuki gs550 carbs, suzuki gs550, needle valves

Question
all factory settings for needle vales on all four carbs have been lost can you help, or give me a starting point? Any answer is worth a 10. Thank You

Answer
Normally the air needle valves are turned in fully, and then turned out 1.25 to 1.75 turns.  These settings should be given in your manual.  Most importantly, all internal parts of the carbs shuld be spotlessly clean, and watch for perforated membranes.  Good luck,  Jan