I purchased a 198x Univega Grand Touring a few months ago, with a busted rear hub. I got that fixed, so it's good to ride now, but I cannot backpedal. When I ride, if I backpedal, the chain just flops down and hits the chain stay, however, if I'm pedaling and then coast, the chain will act like it's supposed to. Is this indicative of a bearing that needs servicing in the freewheel? As I'm typing this, I'm thinking that since the spinning wheel doesn't impact the chain, it might be a jockey wheel on the rear derailleur that is gummed up? Am I on the right track?