With my heli's, I fly with a weighted klunk and a thin walled tube to allow the klunk to follow the fuel around the header tank. Getting into jets now I see a lot of people use juat a straight peice of brass tube with a stone or felt as the klunk, but it does not follow the fuel around the UAT. i think the theory is the placemnent of the pick up point of the klunk should always remain in fuel.
Interesting theory and from most accounts it works but I am interested in some more opinions.....
Can anyone champion the virtues of one over the other?