Thanks again for the replies, I got the bike running decently once I tightened a screw above the idle. It looks like the screw is connected to the throttle (just as a temporary fix). I would probably have to replace the carbs inner connector thing right? It doesn't look like the broken idle piece is a separate part from the carbs.

 

@Fed1016 No, it's not a separate piece. It is permanently attached to the brass shaft. Getting a replacement carb body for the #3 carburetor is what you'd most likely need to do. The missing part is that tab circled in red. That is what the idle screw presses against to adjust the idle speed.

 

Well spotted idodirt ​​​​​​. My initial thought was air leak but yeup never seen a carb do that!