Well
On the even of departure for the annual gathering of the restorer's clubs the bean can failed. In fairness it was not the infamous hall effect, the wires coming out of the bean can had simply flexed once too often and the power supply wire separated.
I pulled it out to fix the wiring and in the process I discovered that the advance/retard pivots were shot and that the upper bush had a lot of movement due to lubrication failure.
As this happened quite literally the evening before departure I was simply out of time and took the GSA instead.
This morning I pulled the bean can out intending to fix it. I would have to remake the pivots and drill the bob weights and fit a brass sleeve in order to return them to stock specifications. The sintered bush is an easy replacement, my local bearing shop lists a suitable candidate for adaption.
I have two dead bean cans but on inspection the advance/retard mechanisms in both are pretty much shot, the buses in both are in good condition.
After a few minutes contemplating a mix-n-match to build a bean can I decided not to bother, and here is the reasoning why:-
There is several hours work to drive out the old pivot pins, make new ones and drive them into the advance/retard plate, and then bore out the bob weights and make a suitable brass sleeve to return them to standard.
I looked at the latest flyer for the Emerald Isle/Red Center/ Alpha 1 ignition system. - Electronic advance and retard, the spindle runs on sealed ball bearings and the hall effect is removable without removing/disassembling the bean can - in fact I am told that a hall effect replacement can be done in 5 minutes.
I contacted the Australian importer and obtained a price. Two minutes later I paid him and am now waiting on the post.
The simple fact is that I have repaired too many bean cans over the years, replacing the hall effect is a bit of a bugger and BMW were out to lunch not incorporating electronic advance and retard from day one (Bosch had/have a near identical ICU with factory programmable auto advance curve.).
When it arrives I post a few photos and provide a report on my impressions.