SRAM XX long cage (XX-A1) derailleur

I loved the SRAM XX when it first appeared.

It had that, weird looking, stooping, b-knuckle. The cable route and cable clamp placing would have been a joke, if they hadn't worked so well. It was an essay in forged aluminium, carbon and titanium. But the most exotic material, magnesium, was reserved for the inner parallelogram plate - the most invisible and forgettable component of the whole derailleur (a part that, on lesser models, is often sneakily made of steel).

Its pulley wheels had silky sealed bearings. Its pulley bolts were not only titanium, they were also hollow. It was completely demountable. It was stunningly light. It was hysterically expensive. So expensive that no one had one.

But best of all, every user-adjustable bolt fitted the same size of Torx key - so not only did you require just one tool - but it was a tool that half your friends didn't even have in their tool kit. How cool was that?

This is a very beautiful example of a SRAM XX (XX-A1) with a long pulley cage.

Derailleur brands: SRAM
Categories: SRAM - X marks the spot where ESP meets DI.R.T.
Themes: Ultra-lightweight - touring/mountain bike
Country: USA, manufactured in Taiwan (the serial number begins '19T2...')
Date of introduction: 2009
Date of this example: week 19 2012 (the serial number begins '19T2...')
Model no.: RD-XX-A1
Weight: 187g
Maximum cog: 36 teeth (SRAM)
Total capacity: 40 teeth? (bike shop lore)
Pulley centre to centre: 93mm
Index compatibility: 10 speed
Chain width: 3/32”
Logic: top normal
B pivot: unsprung
P pivot: sprung
Materials: Aluminium b-knuckle and outer parallelogram plate, magnesium inner parallelogram plate, carbon p-knuckle and pulley cage, titanium small bolts.