I was given a 1990 Cannondale SH400. It has the original front and rear derailer’s. SunTour XCM w/ Accushift 7speed shifters. The owner told me that there was less than twenty five miles on it. When I first took it out I was having problems with the shifter but it may have been just stiff because it started working great. The only problem is when I went to take the chain off to clean and lube, I couldn’t find the master link but did find several of the side of some links fractured. From what I’ve read on here a replacement chain would be KMC 8.93. Before I get a new chain, should I just change out my derailleurs, shifters, and cassette to something better that I can still get parts for? Or is the bike worth that? I’ve seen some posts on hear and elsewhere call it a “cheap hybrid”. If so, is that because of the components? I’m keeping this bike to use so, original parts are not important.