hi there i am new to this and I am having problems with my 250. i put in a new battery in it and it started right up. my son drive it for about 1/2 hour and shut it off. went back out after 2 hour and it would not start i checked for spark and it has great spark. check fuel and has enough fuel. so i do not understand why it will not start. one of my friends told me maybe the cdi box? if you can help it would be great thanks james