You just have to know where to go,
Manchester has:
Snake pass A58 towards sheffield (there is now a speed camera opposite the reservoir though) on a motorbike one of my friends owns the world record for this road average 115 mph average over the 10 mile stretch.
Easy? its not it is twisty AND blind ie you can' see a damned thing around the corners, this is mixing it with traffic and other cars.
I beleive the snake can be taken at 133mph average speed maybe more if the road was closed so you could use both sides of the road.
To the north buttertubs pass, which is a not so good road in the lakes, this is a phenominal road I there is a curved section that can be accelerated into and out of as the apex comes early, which turns into a straight, if you can hit the bump at 132mph EXACTLY you will catch 3.2 seconds of air, which is enough to completely jump over the bridge, though this needs a sports bike as you have barely ANY distance to slow and take the next corner which cannot be taken at more than 90mph.
To the northwest is the Kirkstone pass, slower but nice and less dangerous.
To the South there is Holmes Chapel, to the South east there is the Cat and Fiddle death road (this road has consitantly claimed the lives of bikers for years such that there is a blanket 50mph speed limit on the road).