Abstract: The present invention provides a bicycle front derailleur mountable to a seat tube of a bicycle frame for fitting a chain around a selected sprocket of a multiple chainwheel by pushing the chain laterally at a portion thereof advancing into engagement with the chainwheel, the front derailleur comprising: a fixed section fixed to a bicycle frame, a chain guide for contacting a chain to shift the chain, and an actuating arm and a linkage rod disposed between and pivotally connected to the fixed section and the chain guide. In the above construction, the present invention has achieved the intended object of providing an improved bicycle front derailleur capable of reliably effecting a change speed operation with the aid of a sufficient restoring force of the return spring and achieving minimized in operation forces required for various change speeds.

Abstract: The present invention is a dual-detent shifting apparatus, comprising a supporting seat, an actuating piece, and a detent piece. The supporting seat has plural cable-winding positioning slots and plural cable-releasing positioning slots. The actuating piece is pivotally connected to the supporting seat and has a cable-winding detent suppressor and a cable-releasing detent suppressor. The cable-winding detent suppressor and the cable-releasing detent suppressor may be axially rotated with the actuating piece synchronically. The detent piece has a cable-winding detent and a cable-releasing detent. When the actuating piece is rotated from cable-winding position to cable-releasing position, the cable-winding detent suppressor may drive the cable-winding detent away from the cable-winding positioning slot and the cable-releasing detent suppressor may then drive the cable-releasing detent to be inset into cable-releasing positioning slot.

Abstract: The present invention provides a bicycle front derailleur mountable to a seat tube of a bicycle frame for fitting a chain around a selected sprocket of a multiple chainwheel by pushing the chain laterally at a portion thereof advancing into engagement with the chainwheel, the front derailleur comprising: a fixed section fixed to a bicycle frame, a chain guide for contacting a chain to shift the chain, and an actuating arm and a linkage rod disposed between and pivotally connected to the fixed section and the chain guide. In the above construction, the present invention has achieved the intended object of providing an improved bicycle front derailleur capable of reliably effecting a change speed operation with the aid of a sufficient restoring force of the return spring and achieving minimized in operation forces required for various change speeds.