Patent ID: 7207912

Claim:
A shift control apparatus for a bicycle having a plurality of front sprockets and a plurality of rear sprockets, wherein a front derailleur shifts a chain among the plurality of front sprockets and a rear derailleur shifts the chain among the plurality of rear sprockets, wherein the apparatus comprises: a shift unit that provides signals for shifting the front derailleur and the rear derailleur; and a prohibiting unit operatively coupled to the shift unit and providing signals so that the chain is prohibited from engaging at least one prohibited sprocket combination comprising at least one of i) a laterally innermost front sprocket in combination with a laterally outermost rear sprocket, and ii) a laterally outermost front sprocket in combination with a laterally innermost rear sprocket; wherein the prohibiting unit detects when the front derailleur and the rear derailleur are positioned such that shifting the front derailleur or the rear derailleur to execute a shift command would cause the front derailleur and the rear derailleur to engage the at least one prohibited sprocket combination.