Originally Posted by
jethro56
The biggest hurtle for beginning mechanics is component identification. That's why I suggest posting pictures. Some parts are pretty inexpensive. Some parts are wildly pricey. Without an idea of what you have it's very difficult to advise you on how to proceed.
True. Thinking about it, the comment about friction shifters makes me think "old 10-speed". (Were there mountain bikes sold with friction shifters?) That means probably 120mm dropout spacing and a 5-speed freewheel. A new replacement freewheel is about $15 on Amazon.
If the chainrings are shot, it will be harder to find parts. (Although driving around on garbage day in the Spring will probably yield a bunch of donor bikes that people are getting rid of as part of Spring cleaning. In fact, you could probably find a decent replacement back wheel complete with freewheel that way...) But it sounds like they might be salvageable. I would try to straighten out the bent teeth and see what happened before replacing.
If the freewheel is in as bad shape as it sounds, I'd think a new chain is a given. So, if the chainrings are still usable, we're looking at a total of about $25 in parts to get this running decently again.