From the French Revolution onward, there's lots of proposed and actualized revolutions based around reason and enlightenment, liberalism and democracy, marxism, feminism, theocracy, anarchism, and so on.
There are power struggles and governments and social systems toppled prior to the French Revolution, but these seem to all be mere struggles between competing groups of people for power, there's nothing ideological or idealistic about them. If society is changed, it's more for pragmatic reasons than philosophical. The English Revolution is a partial exception, but that was initially motivated by a power struggle between parliament and the king, not grand ideological motivations.
So, what changed? Why is the idea and sometimes actuality of ideological revolution and the ideological remaking of society present in the western world pretty continuously from the late 18th century on, but prior to that not so much?
I find this question a bit oddly proposed. As any revolt is more or less, ideologically founded. And so I find it weird that you somewhat exclude the 'Religious' revolts, which were Ideological, and by that basis, influenced heavily by Reason, and the desires of the Common Man.
As such, while Historians can give you many examples on Events, and Revolutions, the primary concepts of this question lie more heavily in Philosophical thought, and what you consider to be 'Rational Revolutions'. As I'd say a good majority of Peasant Revolts, while almost never successful, are generally, always fought for the dissolution of an Established Government, for the purpose of introducing a new Leadership which better supports of the Ideals of the people. And these Revolts tend to be Religious, such as the Hussite Wars. Though some sought to end the Feudal Societies, or foreign Hegemony.
On that note, I would say that the dawn of it all, began with the downfall of the Holy Roman Empire (which was, coincidentally, finally put to an end by the French Revolution [following Napoleonic Wars]) As when it comes down to it, and sorry to offend any Catholics who think otherwise, The Revolutions we describe were all initially combating the Power of the Church, to control the way in which people practiced their faith, as well as in the combating of the Power of Monarchs, who were seen as Divinely privileged, all kind of mixed up into that mess.
As such, I'd say Ideological Revolutions begin with Philosophy (much like the French Revolution did, however the French Revolution was more focused on Secularism [but don't let that cloud the overall intent of ideological revolts. A Philosophical change in the mindset of the people, who seek to overthrow the governments enforcing otherwise]) John Wycliffe and Jan Hus are the guys to look to, as the leaders of this entire movement. Which began with Hus' execution, and the subsequent Hussite Wars in Bohemia [1419 - 1434] and the Dutch Revolt (80 Years war) [1568-1668]. Now, both of these Revolts could be seen as reactionary, rather than idealized prior to conception. But so was the French Revolution is a variety of ways.
To best answer your question. It has always been a continuous experiment, of sorts, that as Philosophical thought more developed, and was better able to reach the ears of others, and to expand, particularly as more countries became Protestant, and their rights and ability to read to 'heretical prints' was decriminalized (such as non-latin bibles). Revolution has always been happening and I feel they have always been motivated by the Ideology of the Common Good, for the Common Man.
My only point is, that you are placing more emphasis on the French Revolution than needs to be (in my opinion). It was merely the greatest climax of revolution at the time. So we can best look at it, as a series of Revolts, and the blocks they had to knock down before they could tackle the next one. The First Block was always the Catholic Church. The Second Block was Divine Right of Rule (Populace Governments over Monarchies). And the most recent block, was the Socialist Revolutions (The people against Power from the Control of Resource [whether that be capital, or labour, etc..])
Forgive if I may be missing the point of your question, or if you think I have avoided it entirely. And I apologize for not going more into the modern thought and Practice of Revolution.