I just picked up a miyata seven twelve (number is written not 712) for $110. From what I have read this must be an 87/88. It is full 105 with biopace rings. Its a six speed freewheel (not cassette as I erroneously stated originally) and has the break cable routed inside the top tube. It is black with a teal front end if that makes a difference. I think the tires may even be original, they are labeled miyata. the bike looks like it was not ridden much at all but lubed with motor oil.
My question is does the written number mean something in terms of what year it is?
any insight would be appreciated.
G