Shhhhh. Quietly now. The original derailleurs were long ago replaced with Suntour, Vx front and a VGT-Luxe rear. I did just notice that the rear has some play but it shifts cleanly so it should last a while yet. (Whispering: I currently have an ebay bid on another.) The wheels have also been alloy w/Shimano hubs for a long time. Also the seat post has long been an alloy Simplex.

Next upgrade? I dunno'. Pedals perhaps? Not much other steel left on it. I have a pair of Lyotard platform pedals but I don't think they are especially light and so far I find the originals comfortable. If I found a good cheap alloy pair, maybe...