Carb weirdness identification

[97tiger885]

Riding in dusty situations, I have noticed that the throttle is "sticking" between 3000 and 4000 rpms.  Pulling in the clutch and rolling off the throttle results in the rpms hanging for a few seconds if I am between 3000 and  4000 rpms.  It then  slowly returns to idle.  If I am running at 5000 rpms, it returns to idle normally.   After I return to pavement, the problem goes away in time.   It might take 2 miles; it might take 50 miles.  This seems to depend on the amount of dust.  More dust, more time.   I am managing the situation by rolling off the throttle and delaying pulling in the clutch for a few seconds.  Any ideas what is going on here?

[Mustang]

1 )when were the valve clearances last checked

2) Look for an air leak around the air box if you just did service on the filter .

3) when was the last time the carb sync was checked

4)  have you verified that the linkage on all three carbs  isn't hanging on 1 or more carbs

5) the fuel pipe is a pretty close fit to the carb linkage and I have had that cause the exact same problem you describe cuz it was rubbing on the linkage

6) could it be time for a new throttle cable , look for a break in the plastic housing where it comes out of the twist grip  , been there done that  on Mrs. M's 95 , was the same symptoms you describe