Originally Posted by
jskita
I have this "Bridgestone" frame that I got off CL as a beater. I really wasn't concerned with the brand at the time, because of the goal. A few times I wondered if it was a Bridgestone but since there was no tubing stickers or even a model or name I figured someone just slapped some Bridgestone stickers on it for the heck of it.
The serial says J41718(or 6)2. Though it looks like some of the numbers that have been related to other Bridgestone's in this thread, when I throw in the Gregorian, Fortnight or Imperial Japanese thing then it doesn't make sense
Can anyone help me ID this frame?
The serial number format is consistent with Bridgestone, though it could be Bridgestone contract manufacture, as opposed to Bridgestone brand. The serial number format could also be interpreted as Miyata. Assuming it is Bridgestone, the serial number, in conjunction with the short dropouts and top tube cable tunnels, should make this mid-1984 manufacture. The lack of down tube shifter bosses suggests entry level and further evidence of this status is offered by the flat cut seat lug, steel headset and lack of finishing at the stay to dropout transition. However, I am surprised to see a forged dropout without a hanger, given the apparent era. Still, I see that it's single speed, so we shouldn't rule out the possibility that the hanger was removed and the frame repainted as part of a conversion. Given the apparent era and level, I'd assume it was designed for 27" wheels? What brand are the dropouts? What size seat post does it use? It may not help but I'd appreciate an overall picture.