You're allowed 20% inaccuracy on your speedo so you could say "I admit I was speeding but my speedo definitely said 85mph, not 101 (this would be roughly +20%...I think). If you stick to your story they should have to take your word for it as they should allow for this inaccuracy on your speedo. You'd still get fined but it would be a lesser punishment.
I've heard of people saying this and getting away with it as speed cameras are often inaccurate anyway.
I've heard of people saying this and getting away with it as speed cameras are often inaccurate anyway.