Originally Posted by
GrayJay
Google research indicates the frame is made from "Easton ProGram DB aluminum", most likely a 7000 series alloy (which can usually be TIG welded and then aged to restore the hardness.)
I think that entirely replacing the downtube and bonding in a replacement would be more difficult that it might initially seem unless you are very experienced with using epoxy. Longevity of a re-bonded frame would be highly suspect. Many of the bonded frames from this era had ongoing problems with the joints separating, probably why the bonded-metal construction process has largely been abandon for newer bikes.
I once attended a lecture by mr Burke. He stated the first years production had issues but they got it figured out. I've seen some where all the paint blistered off from corrosion. I assumed those were the first year models he was referring to. Our local coop has had quite a few pass through that were all in good condition.
I found the specs for this model.. Posted above. Alcoa 6061 T6.