(from ebookjapan):

It is a near future where the sound of engines has long since ceased to be heard from the ground and a motorcycle ban has been imposed. If one rides an old-fashioned motorcycle and uses an old-fashioned weapon to defeat Zella Zehnder, the commander of an armored brigade, the motorcycle ban will be lifted and he will be free to ride and travel freely.

However, there were no moving motorcycles anywhere in the world anymore... Saber Serazard, a beautiful woman who is still determined to defeat Zera, hears from an old man, Shin, that there is a motorcycle that will work with just one more breath...?