There’s something about French touring derailleurs after about 1960. Just one look at this Simplex SJ810 GT is enough to fill me with a crushing sense of despair. I can almost hear the chain hysterically clattering on the inaccurately cut teeth of the wide ratio Maillard freewheel as the SJ810 GT pathetically attempts to find bottom gear. I can almost see the bemused expression on the face of the owner of a Peugeot tandem as I attempt to invent a reason why a seemingly rational company like Peugeot had chosen to fit his relatively demanding machine with a poorly constructed derailleur with plastic parallelogram plates.
At heart the SJ810 GT was a Simplex Prestige with a long pulley cage - not a very promising foundation. And all that lack of promise was fully borne out - the SJ810 GT was heavy, unreliable and changed gear particularly poorly.
Even Edith Piaf would have regretted producing this dog.
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