I did this once where it took ages to get anywhere.
Usually the AI trades like mofos so I get dragged quickly, but sometimes not dependingt on 2 reasons.
1: The AI doesn't know each other (because your on an achipeligo world). This situation I try to foster to give me time to build lots and sell lots at disgusting prices.
2: They are all tied up in war with each other and can't afford to research. There are always a few civs that never bother to research anyway (like japan) perhaps you by chance are only playing with these civs?