You often see the claim that single pulley derailleurs were ‘frictionless’. Next stop - the perpetual motion machine.

The Osgear Empire was a Super Champion Champion du Monde, rebranded for the UK market (and possibly other English speaking markets).

• Publisher: Cycling
• Country: UK
• Date: 1939
• Derailleur brands: Osgear, Super Champion
• Derailleurs: Osgear Empire, Super Champion Champion du Monde