I see what appears to be an S.V. on the upper fork blades? That immediately makes me think Super Vitus but I wouldn't expect that with a Tange BB shell, unless the forks are a replacement. Anything stamped on the steerer tube? Fork and bottom thread standard? Seat post diameter? Dropout brand and model? Rear dropout spacing? Front derailleur tab? Pump peg? Dual sets of bottle bosses?