Changing the original gearing, continued.
If the rear hub is a cassette hub, it will be a Uniglide. Maybe later on some would take both UG and HG, but not the earlier ones. Uniglide was replaced by HG and cassettes are limited. You can modify the body with a Dremel to take a HG hub or replace it with a new HG hub. Replacement is better. The new one costs about $20 and you can get a 7 Speed body. Easy to do and How to videos online.
