I'm checking around for a used fluid trainer. I've been checking craigslist and have seen a few decent onces but when I go to look at it should I be looking for anything specific? I know that they will leak if they've been dropped, but how can I tell if there's something wrong w/ it? I'll definitely try it out before I buy it but is there anything specific I should be looking for?
try it out and see if it leaks, there is nothing really to look for except for the obvious, signs that its been dropped such as flat spots or major scuffs, etc.
just use your good judgement, and when you ride it just try to pedal faster in the same gear and it should feel as though its getting harder without shifting any gears, if it doesn't then something is wrong with the trainer.