That's a Kirk precision frame. Cast magnesium. There was a local pro rider used to have one as his team bike on our local chaingang. I nearly bought one in the eighties. They ran over one with a truck on Tomorrow's World and it survived! I had their sales brochure, it said there was enough magnesium in one cubic meter of sea water to make one frame!Just thinking of how to get away from using tubing, but I'm aware that it probably can't be beat for weight and strength.
One mass produced frame was made using die casting but it didn't catch on. Seems like a way to manufacture frames cheap and quick and eliminate welding by hand ?
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