Ok I am a beginner I'm 14 about to turn 15 I'm 5 10 and weigh a 140 pounds and I'm looking to get a Dirt bike but I have no idea what kind or what size to get I can not spend anymore then a thousand dollars and I am exceptionally good on anything with wheels when I was young and my training wheels were took off I literally got on and rid without falling first time so balance shouldn't be a issue