In rural areas the plod are very thin on the ground. In my experience they are quite lenient to motorcyclists and invariably polite and friendly - right up until you get on their bad side.
Bear in mind that the powers of a Gendarme are way above what a UK police could even dream of. They don't need a radar to do you for speeding, just the opinion of two officers, if you can't pay a fine on the spot they'll immobilise the vehicle or tow it until you can (and charge you for storage), their word is, for all intents and purposes, law.
Their response when you are stopped depends very much on your attitude. If you act the cock, they can ruin your day in a big way, if you're polite and accommodating they will be the same and you'll be on your way in no time.