I believe that the DNP GX series were friction derailleurs, while the DNP Epoch series were index compatible. I have never been able to detect much difference in geometry between the two - but who am I to say.
Using the Geological definition, an ‘epoch’ is a span of time smaller than a ‘period’ and larger than an ‘age’. Which reminds me of a driving instructor who sternly informed me that you should use the hand-brake when a ‘pause’ becomes a ‘wait’ - very handy information when you have a driving test to pass.
Despite these musings, the Epoch 6 remains a strongly constructed, but creativity-free copy of a Shimano Tourney.
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