the lowest speed limit in Spain for a car is 60KM and the maximum 120km with exceptions from 120 below there are cases but never up to 120km, thats the top, then on rural roads it depends, 70-90 and when you are going through a town or a city the limit is 50.

That's quite dangerous 80 km/h on these roads Very slow indeed. Here the minimal speed on these roads is 70 km/h (120 max) but usually the slowest lane goes at 90-100 at least.
Some areas are limited to 90 km/h. There is a long bridge in the north of Brussels where the speed is limited to 90 for cars and 70 for trucks: sometimes if you do "only" 90 rather than 100-120, you have trucks behind you that flash their lights because they find that you drive too slowly

did you know that here in Spain, us (people with less than a year of driving license) must keep the speed under 80 KM/H on a motorway ( i never respect it) i find it so ridicoulous, it is very slow to go at 80 on a motorway.

51-52 neither, 52-53 neither, etc. Limit has to be placed somewhere France set it at the speed+1, so you have to drive below the max speed rater than driving aproximately at the max speed as everybody does in other countries

We have a tolerance as well, yes theres a limit but you sometimes cant help reachen the exact limit, and besides, between 50 and 51 there is not much difference

Yes it is. They started to apply that recently I think.
If the limit is 50, it means that you cannot make more than 50. Else where is the limit? If you are fined only above 60 km/h, why is the limit 50 rather than 60?
(though that I am happy to have 6 km/h tolerance in Belgium)

In France it is the case really? for just revasing a kilometre? i dont believe you

In France it is the case.
In Belgium there is a 6 km/h tolerance.
It was just an example, I could have said 60 km/h.

Well honestly i dont know for Belgium but in spain nowbody is sanctioned for going at 51 in a road of 50

And yes by far the first one is more dangerous.

Time, weather, etc.
Sanction, yes, but which one?
Same sanction for 51 km/h than for 151 km/h? (on a 50 mk/h road)
If sanction only depends on the number of excess km/h, is it normal to have the same sanction for 60 km/h in a 30 km/h zone than for 150 km/h in a 120 km/h zone? First one is way more dangerous, no? Especially if second one is done when the road is empty.