It's rare that a derailleur is wildly innovative, beautifully constructed, artistically styled and decorated with sophisticated branding. It's almost too decadently rich a dish to consume - and that's before the waiter brings the bill.

The ROTOR Uno was all of those things. It was ROTOR's first hydraulic derailleur. It was aimed squarely at the road market. It was an 11-speed system generally shown with a double ROTOR (of course) chainwheel. To my eye, it seemed perfect.

The 2013, Acros A-GE hydraulic derailleur was, what it is now fashionable to call, a 'Desmodromic' design with an unsprung parallelogram and two hydraulic lines operating the derailleur, one for each direction that the parallelogram moved. This is also the basic principle featured in Simplex's 1951 patent for a hydraulic gear. As is their wont, ROTOR chose to depart from this model, and used a single hydraulic line, a sprung parallelogram and a complex, sophisticated and precision machined indexing mechanism built into the rear derailleur. This mechanism is inside that drum shaped object at the rear of the derailleur - the stylistic grandchild of the drum on the 1975? Bridgestone Synchro Memory Shift. You can get an idea of how it works in the film ROTOR released of their later ROTOR 1X13 model.

And what happened when all this astounding technology was unleashed upon the world. Well... precisely nothing.

I found the lack of interest to be as impressive as the technical wizardry. I don't think that I have ever seen a ROTOR Uno on a bike that was actually purchased by its rider. On several occasions in the late 2010s I was in Lanzarote, during training camp season. As I trundled along the stunning roads through the lava fields, I was passed by riders using every type of ludicrously exotic equipment... except the ROTOR Uno. Too decadently rich a dish to consume.

• Derailleur brands: ROTOR
• Country: Spain
• Date of introduction: 2017
• Date of this example: unknown
• Model no.: unknown
• Weight: 219g
• Maximum cog: 32 teeth (based on the biggest cassette in the groupsets)
• Total capacity: unknown
• Pulley centre to centre: 65mm
• Index compatibility: 11 speed
• Chain width: 3/32”
• Logic: top normal
• B pivot: unsprung
• P pivot: sprung
• Materials: largely CNC aluminium with a plastic b-knuckle cover and carbon pulley cage plates

Ref. 1574