This is likely the best known of the bikes marketed as a Magnesium frame, but I think lots of bikes were built with some kind of magnesium alloyed tubes. I always assumed Bianchis mangalloy stays had some percentage of magnesium in them. Wonder how many more times I can get magnesium in this reply to a post about magnesium?
I do agree the bike the OP links to is way over priced. It is likely only rare because that is the only one the seller has ever seen out in Hooterville.
Kirk Precision. These were a cast magnesium (one more) and were targeted at the TriGeek market in the late '80s.
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk