I am posting this for a friend who has a Yamaha SRV with pipes and adjustment screws for jetting on the carbs. Does anyone know how to set these up properly? They have a + and - on them I assume for rich and lean, but he is very leary about touching them without knowing how to tell which way to go or if he is doing things correctly. Anyone seen this setup before? The pipes sound good but the sled runs pretty boggy and peaky most of the time.