I was gifted this yesterday. 25”, my size. I planned on giving it a little fluff but now I’m not so sure. The chain is very worn as are the rings. I have a 5 speed freewheel but the chance of me coming across a crank that will work with this is low. I don’t want to bother replacing the tires and cables if I need to replace the crank on a Hi Ten Schwinn. Too much investment. Would replacing just the chain make sense here?