Originally Posted by
bikingshearer
If the fixed cup is right-hand threaded, it ain't English. Right-hand thread fixed cup plus 68mm wide shell = either French or Swiss, and I believe French. They have the same threads dimensions, but one is right-hand threaded for the fixed cup and the other is left-hand threaded. I think right-hand threaded means it's French - maybe someone can confirm this.
Your suspicion is correct: a right-hand threaded fixed cup means "French" thread. Both French and Swiss thread bottom bracket cups are threaded 35mm x 1mm, but the Swiss thread fixed cup is left-hand thread like English.