I think this is a slightly later example of an drop-out mounting SunTour 888 Wide derailleur. It does not have the bijou enamelled name plate, but instead is stamped ‘Sun Tour 8.8.8.’. It is otherwise extremely similar to my ‘2nd style’ example - even down to the weight being within 2g. I think this example was probably manufactured by Iwai.
The underlying design remains a version of a Huret Competition - albeit with very ‘touring’ dimensions and the top pulley concentric with the sprung pivot. The sprung pivot is a full 95mm from the hub axle centre.
Overall, it sets the tone for four decades of SunTour long cage derailleurs; it is strong, simple and well made.
This particular example has suffered a fate familiar to many of us - the chain has got stuck, possibly behind the freewheel, and has yanked open the axle fitting slot (and probably also the frame drop-out). An expensive and painful business.
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