Motocrossed

My heart was racing as I saw the checkered flag before me. I went quickly around the corner, and heard my brother cheering. I had won. I had won for not just my brother, but for myself. But it all went quiet. I made a mistake, and took off my helmet. The 17 time winner said "Is that a girl?" I looked at him and gulped, "Yes. I am a girl. And I just beat your ass."