You are quite right Muskrat, there is a hole where you indicate. It goes through to the outside, half is covered by the cork dynamo washer and the other half is open. Chaterlea, thanks for reminding me that these forums can go way to deep and very quickly.
The hole Muskrat pointed out could well be the source of the oil leak, as when I started the bike up from cold there was no leak and even after about five miles there was still no leak. However after about twenty miles when I got home there was quite a leak going on. The leak stops as soon as the engine stops. So it may be that it took some time for the dynamo compartment to file to the level of Muskrats hole before leaking out.
My conundrum now is Two fold, 1/ why is there a hole 2/ why is oil getting into the dynamo compartment as I thought someone said it should be dry in there.
This sort of takes me back to the idler gear bush!
This might be a good to time to let the forum know why my nick name is ratchet, it is not because I am any sort of machanic, quite the opposite actually. I had bought a new pro socket set from Halfords And was going to take it back because the sockets would not come off the square drives, I mentioned this problem on a Harley-Davidson forum that I was a member of and was promptly hold that I needed to push the button on the top of the drive to release the socket, from that point onwards my nick an was ratchet Richard.
In my defence the last socket set a bought before the Halford one was in 1977 and they didn’t have lock buttons on sockets.
So please be patient with me as I have to do a lot of research to find out what all the terminology refers to like idea gear bush scrolls.
Really enjoying the challenge though.
Thanks again for all the input.