Thanks for the replys guys.
Not worried about damaging it as it's going to be replaced
seems to have a very large bolt hole, much larger than the one's i have ever seen.
I can only assume it's one from a D/H bike as the steerer tube is one from a Z1.
Not worried about damaging it as it's going to be replaced

I can only assume it's one from a D/H bike as the steerer tube is one from a Z1.