Yes, Steve is correct. Karpador, what you are seeing is simply the effect of the "snapshot" rendered at each frame. Depending on the speed the wheel is rotating vs. the number of frames-per-second you are getting, the wheels may appear not to move or even rotate backwards a little bit. For example, if you are getting 60 frames per second and the wheels are rotating at 60 (or any multiple of 60) RPM, the wheels will appear to not be rotating at all because at the instant each frame is rendered the wheel is in exactly the same point in its rotation. This effect is commonly seen on video footage.
Also, to reiterate what Steve said, for any future bug reports please provide as much information as possible when describing the problem. Thanks.