I've spent the last two days searching old topics for the answers to the following questions, and haven't found them: :technical:
1. What parts of the carburetor need to be lubricated after a cleaning?
2. What lubricant should be used?
3. What happens to the air/fuel mixture when i tighten (if you were looking directly at the screw, turning it clockwise,) or loosen (counter-clockwise) the mixture screws (the little ones, not the idle adjustment screw.)
4. How do I know when I've set the mixture screws correctly for my GS500? What do I look for that would indicate whether I should change the mixture one way or the other?
5. How many turns of the mixture screw would be considered excessive?
Thanks in advance for the assistance.
Carbs generally don't need any lube. The mixture screw only has effect on the idle and barely off-idle mixture, anything above that is controlled by the jets. Turning in in makes it leaner, out makes it richer. A good starting point is 2.5 turn out, i.e. 2.5 turns CCW from all the way in. When turning the screw in don't use much force, you want to just lightly bottom it before unscrewing it the 2.5 turns.
See this site for carb tuning.
http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html
2.5 turns is about what the factory uses.More than 3.5 turns and there is something else wrong with the carbs.Probably incorrect jetting.I don't lubricate anything on my carbs except the chokes.I use wd-40, but only if they become sticky.It really doesn't lube them,it just cleans the crude off them.