Yes correct.An interesting point here is that in my collection of Burman clutch plates I have a thick plain plate that has the splined section thinner than the plate section to allow the stack to be position slightly nearer to the chain wheel, maybe to stop the top plate coming out. Also the shoulder at the rear of the clutch centre can be too thick and I have had to slim this down in the lathe to make a stack fit. Finally if you buy clutch springs at a show there are at least 2 or 3 different lengths available, if I remember correctly the difference is whether the inserts are cork or Ferodo, I use the longer prewar type and I can now squeeze blood from a stone. .John
I,too, have this extra thick recessed innermost plate. I was told it came from an early AJS 7R which used a Burman gearbox. It is very stiff but because of the recessing it stands no more proud than the standard plate.
Hugo