Shock-absorbing seat stay for bicycle

A shock-absorbing seat stay for connecting a seat tube of a bicycle, the shock-absorbing seat stay comprising:

• a seat tube connecting mount made of fiber reinforced material and having a seat tube connecting end for connecting the seat tube of the bicycle, and a first coupling portion with a first through hole;
• an extension member made of fiber reinforced material and having a connecting section and two branches integrally extending from the connecting section, wherein the connecting section has a second coupling portion, which corresponds to the first coupling portion and has two connecting lugs each provided with a second through hole, and the connecting lugs are respectively located at two lateral sides of the first coupling portion in a way that the second through holes are aligned with the first through hole;
• a shock-absorbing member made of elastic material and clamped between the first coupling portion and the second coupling portion, the shock-absorbing member being a U-shaped member having a bottom and two arms extending from the bottom and each having a third through hole, one of the arms being located between one of the connecting lugs and the first coupling portion and the other one of the arms being located between the other one of the connecting lugs and the first coupling portion in a way that the third through holes are aligned with the first through hole;
• and
• a fastening unit inserted in the first through hole, the second though holes and the third through holes to connect the first coupling portion, the second coupling portion and the shock-absorbing member together, the fastening unit including a bolt and a nut threadedly engaged with the bolt.