Natural balancing forces guarantee that a beginner, physically ready to ride a bike with quick enough reflex and sufficient pedaling strength, will learn to ride a bike in just a few minutes if taught properly.
When you use Pedal Magic the instructions will tell you in minutes the exact point when your child becomes ready for safe launch. The test described here is a quick and easy way to assess a child's general physical readiness and ability to balance a bicycle.
Note: S/he does not have to catch the ball, only come close enough to catching, indicating that s/he has the ability to react quickly.
Propelling bicycle by pedaling requires muscle strength. If your child is very young or small, you may want to check if s/he has the muscle strength to pedal while you hold the bike up.
Do not run or let your child fall, etc. when you do this. You just want to check if s/he has enough muscle strength to pedal the bike. If your child has already been riding a tricycle, or bicycle with training wheels (not a good idea), s/he has sufficient pedaling strength.
If your child passes the reaction and pedaling strength tests s/he will be able to keep a bicycle in balance. However, there is sill the practical problem of being able to handle a bike (such as rolling it, paddling while sitting on the bike to launch oneself without parental help, etc.). It is better to be sure that your child has enough strength to handle a bicycle before teaching bike riding.
If you want to teach your child how to pedal before attempting to teach balancing, it is advisable to use a tricycle rather than using a bike with training wheels. Training wheels do not ensure that your child will not crash and get hurt. Nor can training wheels teach a child how to balance a bike. Training wheels also tend to stimulate and reinforce behavior counter to what one needs to do to keep a bicycle in balance. This wrong behavior taught by training wheels is what keeps many children from learning to ride.