I have some doubts about Oexing's theory. When he first came up with the details of the design I bothered to work out the path length that the moving/compressing part would go through at different angles and I put that on here. It is certainly true that there is a rapidly rising rate of movement, i.e. compression versus angular movement, with the profiles he mentions. However, I need to remind the reader of some other information also on this subject and previously mentioned on here by me. The first of these items is that when John Emmanuel used a stroboscope to view the ESA he noted that it was like a switch in that it went from the base to the top and limit of its movement when load was applied. The second item to be noted is that after Dick Sherwin fitted one of the Australian ESAs to his Knight and sidecar and then had a look at it a few thousand miles later he found that the wear marks on the surfaces indicated that only about quarter of an inch movement was taking place, despite the fact that there was the extra loading of the sidecar. That is the extra number of springs. i.e. more force, was limiting movement to only about 20% of the total that is possible. Removing a few of those springs allowed more movement and, presumably, more shock absorbing. It seem to me therefor that there is more to this than just the profile of the cams. The Oexing/BMW profile gives rise to a rise in force which is more rapid than linear rate spring can impart. The original Vincent and the Australian system give a more linear rise in force exerted with the original one not being able to exert enough force and the Australian one exerting too much. The Series 'D' ESA has more springs, and was therefore capable of exerting more force, but whether it exerts enough would have to be checked by looking at the wear marks on the cam surfaces.
Over to you chaps.