just been looking at this on the piston heads web site, the link is to a site by the person who got pulled for speeding. if you are going to drive in france it's worth looking at.http://www.neillwatson.com/france.htm
it happened to me i recently went to lemas for the moto gp and was gunned at 207kph. 750 euro fine and six month ban
When you get to the police station they never explain anything and if you don't pay on the spot you vehicle is seised until your court case.
Got done in France August last year averaged 103 mph 90 euro fine, had no cash on me at the time. So they kept passport and made me go to the nearest town to get cash, had to drive back to them to get passport back, then took them 20 mins to fill the paperwork out !! This made me seriously late for ferry so had to drive at 120 mph plus to make ferry