Ok, so I've finally got hold of a paralever rear end - from a K1100RS I believe.
Anyway, I have these parts (random image from the web, I shall replace at some point if required)

So I have there - the usual flat spacer, 4 normal wheel bolts and a 5th bolt with a big spacer/cup thingy. Obviously it goes in the middle of the FD output but for what purpose?
I got a wheel with the stuff, and the wheel has a centre cap. The cap fits in and locks in place as I would expect it to. If the spacer/cup thingy is outside of the wheel the trim cap wouldn't fit.
Someone will know :2thumbup: