All this concentration on beefing-up the welding and using stronger bobbins are, in effect, attempts to make the radiator a structural part of the chassis. As the chassis is flexible, this approach is likely to bring its own problems. An old-school engineer once explained to me that if a component wants to move - let it - just control its range of movement. Then you do not create any new stresses and avoid component failure. Perhaps a solution could be a larger hole in the top bracket and a bobbin loosely fitted and free to move. I'm interested to hear opinions.
