The only Graham/Durham connection around that time that I can think of is Paul Donohue's works in Bishop Aukland, which made the frames for Graham Weigh's shop, badged as Graham Weigh (also built some Cougar and Avanti frames for others), but since you have one of his, I presume you know that...
@marc two tone Interesting that your link for Graham Weigh Cycles has the typo of Co Durham in the address...Shotton is on Deeside, N Cheshire, hence the Cheshire postcode. I wonder if it was once actually directly connected to the Donohue company
I think there's a good chance he got the name mixed up and it's either PD or KW. If they also painted the bike, I doubt they'd forget it
I'm hoping to speak to the original owner. Apparently there were a few of these bikes made for a team he rode for. It'd be good to get the full story before I move forward with work on the bike. Its full Sachs Quarz groupset & campag wheels (not currently on the bike)
Considering how relatively obscure the whole question was, that was a remarkably quick turnaround and testament to this forum (the only place worth asking the question)
Even more remarkable it was answered by me as I had no involvement with MTB in the 90's & although I've known Graeme for years it was only last year I found out his bike building history!