ddeand 

I picked up a 1989 Miyata 312 frame and am slowly getting it together for a casual rider (I'll keep my Gazelle for the longer, faster rides). There isn't much info around on the mid/lower Miyatas, so I figured I'd try here. The serial number on the bottom bracket is PQ59549 with the number 58 running transversely. Can I assume the 58 is the frame size in centimeters? Do the serial numbers and letters have any specific designation?



Additionally, I am not sure what to do about this. I am going to install brifters on this bike and will add cable stops where the

forceofnature

I had a Miyata 712 I bought back in 1989. I think the number 58 is the size. Not sure of any other significance to the numbers.

Wish I had kept it it was a decent bike but a little heavy even though it had 105 group. Got it for $350 new. Sold it for $100 then bought it back for $100 and the guy never cashed my check. So I guess he rented the bike from me for $100.00. Bike was sold later during a moving sale.