To function properly, a balance bicycle must be small enough that the rider can walk the bicycle while sitting comfortably in the saddle, putting both feet flat on the ground. The rider first walks the bicycle while standing over the saddle, then while sitting in the saddle. Eventually, the rider feels comfortable enough to run and "scoot" while riding the bicycle, then to lift both feet off the ground and cruise while balancing on the two wheels.
Children as young as 18 months can learn to cruise a balance bicycle within a few hours' practice.
With a balance bicycle, the rider learns balance first, pedal last. In contrast, with a normal bicycle fitted with training wheels, the rider learns pedal first, balance last. Although opinions differ regarding which learning sequence is easier for most riders, it is generally agreed that a bicycle with pedals is too difficult for most very young children and that training wheels may encourage the rider to learn some behaviors which later must be unlearned.