I am supposed to go look at an LT80 today for my 3.5yo. It's a 2stroke automatic with electric start. I think this will work out well for him and myself since he will be able to restart it. I am just gonna limit the throttle amount and him riding it in sand should keep the speeds down until he has the experience.
On a side note, what helmet is he useing? I am trying to find a light weight full face. Think of getting a mtn bike helmet. All the mx ones seem to heavy for him.