This patent, relating to the Resilion Crimson Star, appears to describe exactly how pulley wheel ball races bearing might be designed. This is odd, as the Resilion Crimson Star famously had ‘crimson’ nylon pulley wheels which Resilion claimed had “no bearings or cones to adjust - (requiring) minimum maintenance”. Perhaps this did not prove to be the attractive feature that Resilion hoped.

• Publisher: UK Intellectual Property Office
• Inventor: Desmond Barton
• Country: UK
• Date: UK application filed November 1957
• Derailleur brands: Resilion, Phillips
• Derailleurs: Resilion Crimson Star