I think that the SunTour Le Tech was SunTour’s second foray into the world of three pivot derailleurs (the Trimec (6400?) being the first) - and the Le Tech is a blinder - I particularly like the oh-so-modern ‘computer’ type face.
I remember the Le Tech being presented as a pure touring gear - SunTour’s response to the 1981 Shimano Deore. It was Cyclone quality and combined SunTour’s slant parallelogram with the joys of a three pivot design. It gave a very small and consistent chain gap and a lightening quick and pin-point accurate gear change.
With the gift of hindsight, its most surprising feature is that it had a conventional guide pulley that you could remove and replace. I never knew why SunTour ditched this design and adopted the fatally flawed Trimec configuration for the first MounTech models.
However 1982 was not the time to launch a radical touring derailleur - the tidal wave of mountain bike hysteria was just crashing onto the shores of the bicycle world and the Le Tech got washed away in the turbulence.
A forgotten work of (fragile) genius.
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