Early 90's Honda Nighthawk 750? You could be near right but I suspect it was not called a Nighthawk in Europe.
CB 750 Seven Fifty en France...
Norton Commando "Fastback" With a disc front brake it is 1971 or later.
The tank, tank badges, side covers etc. appear to be 1968 "Fastback" but the front end is off a later model. The picture isn't very sharp or clear but it appears it might have the tach. drive on the timing cover which would also indicate an 68 model. If you look closely you can just make out the tachometer cable off the timing cover.
I want to believe it's a BMW, but I don't see the traditional logo anywhere. Not a stock BMW-fairing, that´s for sure. Either a 80´s Japanese bike or - more likely - some aftermarket fairing on some bike that I can not identify. But it does not look like a BMW anyway !
Kawasaki GTR 1000