Steve,
Appreciate you thought you had good intentions by sharing the video of your son, but you have come across to the forum as nothing less than a lunatic.
I understand every father wants the best for his son, but the course of action will be for him to decide when he is much older. Not yours to decide now.
What you must do is help him "grow" and develop his intellect, so that when he is a young man he can make the best possible decisions for himself.
Rather than pressing your 4 year old son into sport, get him to school and get him educated. Save money so he can go to "college" when he is 18.
(Just whatever it takes to make sure he has better spelling and grasp of the written English language than his father.)
Fine education, exposure to a vast spectrum of ideas and knowledge of the wider world around him will help him choose his path wisely.
Introduce him to sports and exercise as part of having fun, maintaining a healthy lifestyle and how to create bonds with other people.
If he's interested in riding bikes, fantastic. Facilitate that as best as you can without bankrupting yourself, but keep it fun and only if he wants to do it, he shouldn't be told to.
With a strong, educated mind, he can choose whether he wants to choose trials/MX etc to make a living, when he is ready.
All the best
(But, can't resist, as this has wound me up:
- Interest from MX coaches on a 4 year old? Are you mental?
- That moto trials practice will get him no where. He needs to be riding mud, so he learns how to make the bike grip.
- Why is he going around flat corners with his leg up by his handlebars?! He needs to have his weight over the front of the tank, his inside leg close to skimming the track and his outer leg applying pressure to front of the foot peg. I ride MX, trials and bike trial. If you want him to turn pro, at least teach him properly)