The LTWOO RX is a thoroughly competent, but perhaps rather unexciting, top-of-the-range mechanical derailleur. It is 12-speed-compatible and, in this 'R5012 M C' version, features a carbon outer pulley cage plate.

Released in 2021, I see it as the warm up act for LTWOO's upcoming range of electronic derailleurs. The RX groupset allowed LTWOO to get some experience of road disc brakes, road dual-control levers and the fickle world of those opinionated road consumers.

LTWOO did incorporate some original ideas. In particular they stressed that the RX groupset was designed for Asian (and particularly Chinese) cyclists. The levers were optimised for smaller hands etc.. As the centre of gravity of the bicycle consuming world moves remorselessly East, it would be surprising if others didn't follow their lead.

• Derailleur brands: LTWOO
• Country: China
• Date of introduction: 2024?
• Date of this example: 2024?
• Model no.: R5012 M C
• Weight: 223g
• Maximum cog: 32 teeth (Source: LTWOO)
• Total capacity: unknown
• Pulley centre to centre: 90mm
• Index compatibility: 12 speed
• Chain width: 3/32”
• Logic: top normal
• B pivot: sprung
• P pivot: sprung
• Materials: mainly aluminium with a composite outer pulley cage plate

Ref. 2197