Freewheel bottom bracket structure for bicycle, has bottom bracket portion that is not rotated to predetermined degrees, and pedal arm portions which are moved along forward direction through force applied on pedal by user foot

摘要

The bracket structure has a bottom bracket portion (7) that is not rotated to 360 degrees. Pedal arm portions (3) are aligned and are moved along forward direction through the force applied on the pedal by the user foot.