Regina Extra Freewheel or Cassette I have a road bike (Carlton Flyer, 1977) with a regina extra rear cassette. I'm interested in downgearing it (i live on a massive hill) and am trying to identify whether it is a freewheel or cassette and if downgearing is possible - before I start pulling it apart.

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Ideally, I'd like to replace it with the same type, or add an extra ring at the top to give me a climbing gear. Doesn't have indexed shifters so I don't think that would be an issue.

Any help appreciated!
It is a freewheel. You will need the appropriate freewheel tool. The tool typically won't fit without removing the axle. You may also need the correct cone wrenches. This makes it a good time to service the wheels bearings as well. You may want to consult your LBS and compare the cost of having it done versus purchasing the tools you may only use once.