My local bike shop fitted copper shims on my seatpost because they thought it should be ultra tight. The post snapped last week and now they want to charge me 150 euros to remove the bottom half from the frame- mafiosa! Does anyone know if copper is a recommended material for seatpost shims? I have a feeling its not the right stuff to be using in this instance and I'd love to be able to shove that in their faces! CHEERS