Originally Posted by
Dunbar
Cheap mag trainers have very little inertia which means they don't simulate riding conditions on the road. Translation - unless you spend a lot of time riding them they suck for testing FTP.
Even the best fluid trainers do a completely crappy job of simulating riding conditions on the road.
Yeah, they have a better power vs. "speed" curve. For a device that, when working properly, doesn't move at all. How "fast" you go on a trainer is like wondering what color your dog's bark is. It's kinda orthogonal to reality.