I've found that like most things in life, riding everywhere in Europe the 'don't be a d**k' rule applies. If you're riding like a d**k, they WILL pull you and fine you on the spot. Sometimes a very large sum. Never had an issue with exhausts, plate size, visors etc.
Never been pulled over in Switzerland so can't comment as to how strict they are but have had experience in the other countries you mention, in the last few years we've had;
?300 fine in Spain for speeding (85mph in a 90km/h national speed limit zone)
?100 fine in Austria for 'making chicane' as the policeman called it. Basically weaving side to side whilst riding along in town, not sure if the rider thought he'd better keep the heat in his tyres for a fast lap of the Stelvio or what ?!?
?100 fine in Germany for crossing solid white lines whilst overtaking a bus. Could have been worse but copper recognised that the overtake began before white lines became solid.
On another trip, which I wasn't on, one of the lads I know was nailed for speeding in France and had his passport confiscated and bike impounded until trial! Not ridiculous speeds, certainly not over 100mph as he's just not like that, was on his R1200RS. He had to pay for a hotel to stay in the area until a judge heard the case. I can't remember the exact fine but I know it was over ?1000, plus storage costs, plus hotel.....
On the other hand, I've had lots of good experiences with the law over there. 2 of us were nabbed speeding in the Dolomites, 3rd lad turns up whilst they're checking papers and we're trying not to fail the 'ar**hole' test. The 2 Italian coppers lost all interest in us and just wanted to check out his brand new Panigale 'Ah! You like Ducati?'. After that we were let off with a stern talking to and waved on our way.
My father in law got caught on a 'motorcycle prohibited' road in Germany and whilst he was pleading ignorance it turned out the copper was a keen motorcyclist too. 'This road is forbidden for motorcycles, too many accidents. You must leave this road at the next junction, to the left, and it will take you a different route to your destination.....on second thoughts.....take the second road on the left a few km further on. It goes to the same town, but is a MUCH better road
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