Originally Posted by
Kapusta
What the heck is a "generic" rear derailleur?
It's erm...
I am not sure about 6 sp, but as far as 7 sp and above (in Shimano).... ANY 7-8-9 sp MTB or 7-8-9-10 sp Road shifter will shift ANY 7-8-9 sp MTB or 7-8-9-10 speed Road rear derailleur. At least for anything made by Shimano in the past 25 years.
They're the ones. Pretty much everything.
I don't even know what you are saying here. 10 sp MTB shifters and RDs are BOTH incompatible with all the MTB and Road shifters and RDs I mention above. The 10 sp MTB shifter and RD are meant to work together.
So yes, this clutched, Shadow type DynaSys rear derailleur is a different ratio than the 'generic' 1:1 units you mention, which is the whole point. And it won't work as a replacement for a generic rear derailleur on either road/MTB or whatever unless the shifters match.
I was not aware gear numbers had to match, that either DynaSys is only 10speed or whatever. Neither do I intend to find out, as I'm planning on a return to smoother and faster 8speed shifting if I can find a cassette with my preferred ratios in an 8 set.
Incidentally, for those needing to know, the DynaSys logo;