Originally Posted by
joejack951
10 speed triple deraillers however are not nearly as tolerant. of ring differences because of an extended inner plate. This plate will interfere with the middle ring if it too close in size to the big ring.
Deeper inner plates have been around for quite a while and the new 10-speeds are just more of the same. Most fd's, even back into the 7-speed era, require a 10 tooth differential if the clearance over the big ring is set properly.
This is the "feature" that killed off half-step gearing but, of course, 7 and more rear cogs made it far less useful anyway.