When I was considering the 79 CCM, I contacted a supplier/manufacturer in the UK about availability of parts. He indicated the 79 models had a problem with snapping the downtube under heavy compression. He had made a replacement frame for the bikes and wanted $10,000 for one. My head was spinning at that point.
Anyone heard of this problem before. I spoken to the original WA state distributor about it and he'd never heard of it.