This bike has been setting for about ten years. I just got it & put a battery in it & cleaned the carbs. Now the air filter has rotted away. So I went two sizes larger on mains & three sizes larger on the secondaries. It runs great above 3500 rpm. It only idles on one cylinder. I have had the carbs back off & tried to clean them better, but no luck. Any ideas? This is one of those bikes that does not have an idle air screw adjustment & I can't find any idle jets...