Hello, I'm in Derby also, just a thought, you haven't got a large amount t of old chain lube built up inside front sprocket cover have you?? Had a similar problem myself, was put down to over use of the chain lube. Inside cover cleaned and degunged, less Lube used and problem gone.
Are the black drips oil texture?? Or sticky as in lube sticky??
As for Derby mechanics, I have used racing lines many times for other bikes, yet to take my vstrom there.