Where do I find the mixture screws?

I have an 82 750 Seca and when I am riding it will now come down to normal idle very quickly. I think it is running rich? How do I set this and where do I find the screws to set it . I dont know where they are at?

 

Ok, I found them but now how do I set them. Here is my problem. I got the bike a year ago and had the carbs cleaned and the intakes replaced. Now it runs great, cold blooded, but when it warms up it runs great. Except for the idle problem. It will idle but when the throttle is applied it will hag at 4000 rpm and then slowly get back down to normal. 750-1000 rpm. When I am riding it will do the same thing when I put the clutch in or step on it. It is almost unsafe to ride. Is it running rich? Lean? how do I fix this? It has a new cable on it so I know that is not sticking.

 

A colortune will work great to set the fuel mixture properly.

 

Is there a way I can do it myself with out a color tune? What is that by the way?