Rollers are (Click here) an indoor trainer for bikes without supporting it. I have purchased my own, i have a bookcase in the garage I lean on, finally after 2 days of having it have finally spent a few minutes on it without using the support. it uses the same force as keeping a gyro on a balance point, so I have to keep the speed up and not lean or a spin literally off it, i have only fallen off it once. and thats the spinning, somehow the bike spun back to front with the momentum, thankfully I caught myself before i slammed onto the floor.