It appears to be a Black Lightning, which was the factory built racer. The pipes and carburetors are correct. The gas tank is interesting, I've never seen one like it. I suspect that it was for a long distance event, maybe the Manx GP that was held in the fall for amateur riders.
15 BMW RnineT
10 Ducati 1098 Streetfighter S - "Sleipnir"
09 Kaw Versys
67 Triumph Bonneville TT Special