Class Flash ActionScript

package{
  import flash.display.Sprite;
  
  public class Main extends Sprite{
    public function Main(){
        var fixedGear:Bicycle = new Bicycle(1);
       // trace(fixedGear.wheels); //Wrong! Compiler error.
        trace(Bicycle.wheels); //Right! 2
    }
  }
}
class Bicycle
    {
        public static var wheels:Number = 2;
        private var _gears:Number;
        public function get gears():Number
        {
            return _gears;
        }
        public function Bicycle(numberOfGears:Number)
        {
            this._gears = numberOfGears;
        }
    }