The Grey Flash features an extensively drilled and lightened headstock casting.
The Works must have deemed this appearance a little unsightly so an alloy cover plate was devised to cover up the holes and provide a place for the mercury crest transfer.
I’m convinced this is original to the bike; accurately constructing a similar part wouldn’t be hard but correctly replicating the dimensions would require more diligence and it’s very unlikely anyone would have bothered with such a trifling task in decades past.
The question here is what might the original finish of this component have been? Usually they were polished. I feel certain that it wouldn’t have been blasted – some of the visible dings have also been subjected to this treatment indicating that the blasting was undertaken later on in the bike’s life. As the finish/presentation was a very important aspect of this early Grey Flash I suspect this plate would have been anodised along with many other of the aluminium parts. Re-anodising might be one answer or perhaps carefully removing the blasted finish with a suitable grade of wire wool. We need to have a careful think about this before coming to a decision.
One thing we’ve noticed about the drilling on the headstock casting is that it differs from that of later examples. David Dunfey has kindly sent me some images that show a different pattern of 5/16″ holes.