There used to be a guideline that you could drive upto 10% of the stated speed limit plus 2 or 3 mph (can't remember which). so, Posted speed ... Possible max speed 30mph ... 35-36mph 40mph ... 46-47mph 50mph ... 57-58mph 60mph ... 68-69mph 70mph ... 79-80mph I drive around 250miles a day for work - most of which is on the motorway and have noticed that since the Highways Agency patrol's started you see less and less marked police cars on the motorway. This is because the Highways Agency vehicles have been deliberately marked up to look like a police patrol vehicle until you are very close up - so the effect of decreasing the motorway speed to the limit has been achieved at no expense of the local police force. The safest way to avoid a ticket is simply not to speed - the realities of the modern motor vehicle mean that you probably will end up speeding at some point - particularly on 'rep roads' such as the M40. Key things to remember are :- * Don't speed through roadworks - most major route roadworks now (think M6 by Birmingham, M1 by Luton, M25 by Enfield) have average speed cameras to ensure they catch more people - use the C4 speed limiter to keep you legal :lol: * Look for extra aerials on 'normal' cars - most mobile phones no longer require a seperate aerial - so the only people who have need for the 'hedgehog' look are the Police. * Speed limits displayed on central reservation signs or the normal overhead gantries are advisory only - you can excess them without penalty (upto the 70mph max of course <_< ). The only enforceable speed limits are ones shown with a red circle around them (i.e. Roadwork signs, M25/M40 variable speed sections). At the end of the day drive at a speed which feels safe for you, the car and the surroundings - if you are going to speed, respect the other road users who don't want to - but conversely don't try and slow other cars down who are speeding by sitting in the middle or outside lanes at 69mph when you can move over to the inside lane. Good luck and safe driving