CassidyAce
Senior Retro Guru
The four bolt STX RC, like the one you nearly bought, has standard chain rings, with no bolting the small ring to the middle. The five bolt STX and STX RC did have some unusual features.Turns out the chain wheels can't easily be replaced. The outer and inner aren't too hard to replace but the middle serves as the bracket for the smallest one so can't be swapped for a new one.