All righty, let's see if we can make some progress here.
The floats regulate the amount of fuel in the bowl. They do this by lifting or lowering this device called a float needle:
The needle has a small bail attached to it that fits over a tang in the center of the floats, that tang regulates the height of the fuel in the bowl...which is apparently your problem all along:
if the tang is bent incorrectly, as it seems one of yours is, it malfunctions. Here is the proper setting for you to show mechanic #2 so he can set the float height properly and return your bike to good running condition:
