The rear derailleur is no different in this regard ... These should be set so that at the extremes of the derailleur's range, the chain sits directly beneath the smallest and largest cogs ...

Either option offers a similar drop in low gearing, but the cassette and rear derailleur combo obviously adds more range and a bit more flexibility because of its increased chainring options. If you ...

There have been countless innovations to the rear derailleur over the years. These have included compatibility with an ever-increasing number of sprockets, the introduction of indexed shifting ...