I'd like to replace my rear wheel because it isn't able to be fixed to be made true once again. The bike is an older Schwinn Tempo, the rear wheelset has a 6 speed freewheel. Or so that's what the guy at the shop told me. He only had wheels with casettes, and told me I wasn't able to use one of those.
Question is, I'd like to get a new wheelset. Do I have to stick with the freewheel style? Or can I get a modern, casette type wheelset? If the latter, do I need to make any modifications? Adjustments?