This photo was actually taken on the street in front of my house. (Look closely and you can see the reflection of puffy white clouds on the motorcycle.)
Post-production work included the usual exposure correction, sharpening, etc. in Photoshop. Following that, I carefully selected the subject (motorcycle & rider), removed the background, and put the subject on its own transparent layer. Underneath the motorcycle and rider layer I added another layer with a radial gradient (using the eyedropper tool to select colors from the motorcycle).
To make the reflection I duplicated motorcycle & rider layer. Using 'Transform' I flipped it vertically and skewed it slightly to make it 'fit' and then darkened it a bit. I fooled around with it until it looked to me like a realistic reflection. (If I were reworking this image now I would probably add a shadow on the 'floor' to enhance the realistic effect. There's always room for improvement!)