| 摘要 |
<p>The present invention relates to a double speed change bicycle allowing proper riding posture capable of preventing pains in a shoulder, a waist, a hip bone, and a crotch by disposing a pedal in front of a seat tube on which a seat is installed of a bicycle frame, not directly below the seat tube to allow a rider to straighten the rider′s back and ride in a proper posture compared to a case where the pedal is disposed directly below the seat tube, developing muscles and easily transferring a force by allowing the user to pedal like going up on steps to bend the knees and the thighbones up and down and grab a handle while straightening the upper limbs and the chest like pulling the handle, and preventing accidents by securing front view. The double speed change bicycle allowing proper riding posture according to a proper embodiment of the present invention comprises: a first speed changing means having a first sprocket on one side of a front of a bicycle frame, a second sprocket installed behind the first sprocket, and a first chain connected between the first sprocket and the second sprocket; and a second speed changing means having a third sprocket installed on the other side of the front of the bicycle frame and disposed on the same horizontal line as the second sprocket, a forth sprocket installed behind the third sprocket, and a second chain connected between the third sprocket and the forth sprocket. Pedal cranks on which pedals are installed are installed on both sides of the first sprocket.</p> |
