When I go to adjust my idle mixture nothing happens no matter how far in or out I wind it nothing happens. I have wound it all the way out and pumped compressed air through and nothing is blocked.

Has anyone else had this issue?

I had the same problem with the carby on my 1300. I didn't think it was blocked but I ended up taking it to a mechanic who stripped it and cleaned it. Works great now

I had the same issue but instead replaced the carb with a 38dgms.
 
My car ran perfect for 5 years but the carb started to deteriorate to a point where the car wouldnt idle and would backfire. I think it was just the carb being old and needing a kit put through it and a good clean as Eskie92 said
 
A vacuum leak could be why the mixture screw doesnt do anything. Usually if there is a vacuum leak then you will be able to block the top of the carb off with your hand and the engine will still idle
 
Ryan

If the idle speed screw is wound too far in the mixture screw will have nearly zero effect. This is due to the carby running on the progression/main circuit. On motorbike carbs this circuit is roughly 3-4 times larger in fuel flow.

Google tuning weber dgav

Otherwise ****ed carby is a ****ed carby

My idle speed is set only 1 turn in. It's just had a kit put through it. So I might try searching for a vaccume leak....