Originally Posted by
big chainring
I'll check out the Hurets. Just always liked the look of the Simplex derailleurs.
The Challenger and DuoPar are solid units and perform very well.
So Simplex drops arent threaded? Never knew that.
Older Simplex dropouts used an unthreaded 9mm hole. The derailleur was secured in place by a bolt that threaded into the pivot shaft from the inside of the dropout. Many of these dropouts were tapped by shops or consumers to 10mm x 1.0mm to accommodate threaded mounting bolts, and this did not interfere with using an old style unthreaded Simplex derailleur either.
Later Simplex dropouts used standard 10mm x 1.0mm thread and the derailleurs threaded into the dropout in the typical fashion.