Seishun Jidai 1. 2. 3! / Bicycle Daiseikou! (青春時代1. 2. 3!／バイセコー大成功!, Age of Youth 1. 2. 3! / Bicycle Big Success!) is the second single of the subgroup Petitmoni. It was released on July 26, 2000 and sold 484,160 copies. It went to number one on the Oricon Charts in Japan.