Originally Posted by
edwardsmarkf
somebody warned me it might not be that easy on an old Peugeot bicycle. i do remember being told a long time ago that European bicycle manufacturers were extremely nationalistic on their thread sizes.
Older French bikes may have metric pedal thread, but starting around 1980, English/ISO thread was used. Often, pedal thread spec is marked on the crank arm. If you can't find metric thread pedals, the arms can be re-tapped to English/ISO thread.