Getting ready for my next adventure I thought I'd give myself a sporting chance and get the brakes working better as they still were not so good after renewing all the shoes. I did the test of holding the drum on a wire from the centre and tap it with a hammer. If it rings like a bell it should be okay. One drum from the front and one from the rear did not ring true and sure enough I found both to be cracked. So that is three out of four drums replaced because of cracks. I have replaced them with new shadow drums.