Hi, I set up my road bike in a Kinetic road machine trainer and I can't stand up and pedal. The stroke is uneven and I have to fight hard against the 'stop and go' of the pedal, usually unsuccessfully. This happened when I had my mountain bike in the trainer (with slick tires). I'm not sure if this is a trainer issue or a strength issue. I've no problem with this on the spin bikes at the gym or on my bikes outdoors. Help!