With the Crane, Shimano pulled out all the stops in an attempt to make a truly world-class derailleur. It was an all aluminium design with a dropped parallelogram - a world first. The finish was excellent with that anodised ‘glow’ that Campagnolo had perfected. The chromed parts were bright and polished. The pulleys had a two part bushing system so that bronze rotated on bronze. Even the springs seemed to have less of a tendency to lose their tension. All very classy.
Shimano were not backward in coming forward with the price - which set new records for a Japanese derailleur (even if it was still someway from Campagnolo’s extravagant pricing).
The only fly in the ointment was SunTour’s patent on the slant parallelogram. The Crane never changed gear quite as well as the much more lowly SunTour V series - despite Shimano’s puff about the efficacy of their ‘servo pantagraph’ design with its two sprung pivots. This was a particular issue with the long cage versions.
This example of the Crane GS is from the third generation of the Crane featuring a steel cable clamp nut and a redesigned pulley cage with oval slots.