found this link to compute trail:
http://www.kreuzotter.de/english/elenk.htm
I'm getting about ~2cm of trail loss, given an outside tire size of ~28".
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1989 Schwinn Paramount OS
1980 Mclean/Silk Hope Sport Touring
1983 Bianchi pista
1976 Fuji Feather track
1979 raleigh track
"I've consulted my sources and I'm pretty sure your derailleur does not exist"