Originally Posted by
cyccommute
Plastics are something that needs much maintenance. Generally, plastics are thrown away and new plastic is put in its place because plastic is so easy to make compared to other materials.
Not sure what plastic parts you are referring to in your photo. Even if there is plastic inside the derailer, it really isn’t something that needs much maintenance.
It's the most hated of all Simplex Delrin FD's. As the Delrin deteriorates, beyond about the 1963 year, the molecular composition of the Delrin begins to oxidize on its surface, the plastic molecules slough off into the surrounding atmosphere, leaving behind only the remaing metal molecules which cause the lightweight Delrin to lose its low-weight advantage, as shown in this 1962 Simplex version.