Thanks Richard,
I now have the dynamo off, cleaned it out, back together again and it lights a 12v bulb quite easily,its a work of art getting it off in the first place.
What I intend to do next is to trace all my wiring to determine if the bike is positive or negative earth wired and then change it to negative earth.
I will clean down the regulator and reset it to see if everything is working as it should then I will put on a solid state regulator when I have proved the system.
Thanks for all the messages I will keep posting. Alan