Looking at the 1987 catalog, I see some possible matches. The Circuit, Prelude, and Tempo all have a pump peg like the OP's bike. However, I can't remember if any were made in Japan.
Is there a brand name on the fork ends or drop outs?
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Carbon: Fuji SL2.1 Di2.......Aluminum: Cannondale Synapse 105........Steel: Vintage Specialized Sirrus
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