Bridgestone serial number question
 

Hello everyone! Wondering if anyone here could identify a Bridgestone year and model based off a serial number. Mine is K317947 with a larger "7" underneath it. I have a longer describe post but can’t post pics until I get two more posts. (UGH in the 21st century!) thanks!

The subject bicycle was manufactured during a year which has a '3' as a last digit. The Bridgestone serial number format does not contain information to indicate the decade or model. You have to determine them from fame features, components, etc.

Album: https://www.bikeforums.net/g/album/21587152
Photo assist:
https://cimg3.ibsrv.net/gimg/bikefor...00c7ea7d1.jpeg

https://cimg0.ibsrv.net/gimg/bikefor...9ac8e9853.jpeg

A 1983 Bridgestone 400, perhaps? Here's the catalog page from 1985: https://sheldonbrown.com/bridgestone...ne-400psd.html

You folks never fail to disappoint! Thanks so much!! It was at a verywonderful bike cooperative in Corvallis, OR, outfitted with '92-ish Mavic 631 stuff - 53/39 cranks (the "star fish" style, yes), bottom bracket, derailleurs, downtube shifters, and wheels (7 speed
cassette); most of which I sold on eBay to offset the price of the bike. (There's quite a market for some of those parts, turns out.) The
bike had the feel of being original but I wouldn't want to assume anything. It came with a SunTour Superbe headset and Superbe brakes
(single pivot) that "might" be original. The SR handlebars have an '83 date code, as does the SR seat post (27.2mm). It's got a serial number
of K317947 with a larger "7" underneath it. It's set up for recessed nut brakes, two sets of water bottle mounts, fender (but not rack)
mounts. Other than the Bridgestone decals, the frame is marked as CrMo 4130 Bridgestone Quadruple Butted Tubes. Overall it feels similar toan RB-1 or Rivendell Roadeo in terms of geometry and stance.
Did someone buy this bike in '83, and then
update it in '92/'93 with a nice set of Mavic racing parts?

I rebuilt the bike with a mishmash of parts I had on hand - basically making it more suitable for my fitness and the terrain here in the
Portland area. Thanks again for the help!
https://cimg2.ibsrv.net/gimg/bikefor...8b95e8f78.jpeg
https://cimg8.ibsrv.net/gimg/bikefor...420136e08.jpeg

My leading candidate would be a 1984 Bridgestone 700 manufactured in 1983. Despite the similarity in colour scheme, the 1985 Bridgestone 400 came with exposed nut brake calipers and clamp style shift levers, while the OP's has recessed nut brake calipers and brazed-on bosses for the shift levers. The OP's bicycle is higher level but doesn't exhibit the high end features of the Grand Velo models. The frame level is consistent with a 600 or 700 but since the latter was partially spec'd with Superbe, that would my first choice. .

T-Mar, you continue to be a fountain of amazing bike knowledge! We are all very lucky to have someone like you in our community of bike nerds. Thanks!