BCNorwich
As said it depends on your type of bike, you can always walk a bike down there. It's perfectly OK for an ordinary bike (ridden carefully with consideration for the surface) but it would wreck a fancy racing bike. The surface is rough, some minor potholes, and has many flinty broken stones typical of Norfolk. 
It is a PRoW track for foot, horse and bike, used by agricultural vehicles to access the fields. I've walked here many times and verify these facts.