This 66cm bicycle wheel demonstrates the principles of gyroscopic motion.  The wheel rotates on a ball-bearing axle and has handgrips for students to hold while the wheel is spun.  The rubber tire concentrates the mass at the wheel's rim, which produces a strong gyroscopic effect at relatively low rotational velocities.  The protective masonite guards prevent accidental contact when the wheel is being held, and metal suspension loops at the end of each handle allow the wheel to be hung from a stationary support.