The SunRace 598 is a long pulley cage version of the SunRace R80 (R82). It is slightly weird that it uses SunRace's old naming convention (591, 592, 593 etc...) rather than the naming convention that was introduced with the short cage version of this derailleur (R30, R80 etc...).

The SunRace R80 (R82) itself represented a step up in SunRace's capabilities and ambitions. The level of precision and finish was decidedly mid-range Shimano, rather than low-end (or even below-end) Shimano. It was the first of a cascade of gradually improving, fully aluminium, Taiwanese models that heroically strove to challenge Ultegra.

Note that, on this model, SunRace included their distinctive, and pleasantly eccentric, b-pivot adjustment system.

• Derailleur brands: SunRace
• Country: Taiwan
• Date of introduction: 2003?
• Date of this example: unknown
• Model no.: unknown
• Weight: 311g
• Maximum cog: 27 teeth?
• Total capacity: 37 teeth?
• Pulley centre to centre: 87mm
• Index compatibility: 8 speed (SunRace details for R85 with similar design of cage)
• Chain width: 3/32”
• Logic: top normal
• B pivot: sprung
• P pivot: sprung
• Materials: fully aluminium parallelogram with steel pulley cage plates

Ref. 2115