Unidentified Frame - suspect Japanese
03-09-17, 10:37 PM
#1
Newbie
Thread Starter
Join Date: Mar 2017
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Unidentified Frame - suspect Japanese
I just bought an old steel-frame bike for a fix up project. I liked the color, and since all the frame decals are missing, I was intrigued by the mystery. It didn't hurt that it was $60.
This evening I spent pulling the shifters, derailleurs, brakes and seat off. Then I cleaned her up a bit. At first I thought it had a really short serial number. Stamped on the Bottom Bracket is "B30T" - but after removing the front derailleur, I found that there is a serial stamped on the left side of the seat tube near the bottom bracket. It reads "DR10750029". I was pleased to find that the hubs front and rear are Campagnolo Record, and other than being filthy, they are in fine shape.
The front fork is chrome and I suspect that it may not be original to the bike. It cleaned up nicely. On the dropout it reads "TANGE-T". The rear dropouts read "I.S. Rib End". Some searching on the forum for IS Rib End led me to a Japanese tube manufacturer: Ishiwata. However, it appears this company built tubes for an array of manufacturers.
Anyone seen a bike manufacturer who stamps the serial on the left side of the seat tube and an odd 4 character code on the bottom bracket? I'd love to figure out the manufacturer.
I wanted to post some pictures, but I'm a new member and am restricted from posting URLs.
This evening I spent pulling the shifters, derailleurs, brakes and seat off. Then I cleaned her up a bit. At first I thought it had a really short serial number. Stamped on the Bottom Bracket is "B30T" - but after removing the front derailleur, I found that there is a serial stamped on the left side of the seat tube near the bottom bracket. It reads "DR10750029". I was pleased to find that the hubs front and rear are Campagnolo Record, and other than being filthy, they are in fine shape.
The front fork is chrome and I suspect that it may not be original to the bike. It cleaned up nicely. On the dropout it reads "TANGE-T". The rear dropouts read "I.S. Rib End". Some searching on the forum for IS Rib End led me to a Japanese tube manufacturer: Ishiwata. However, it appears this company built tubes for an array of manufacturers.
Anyone seen a bike manufacturer who stamps the serial on the left side of the seat tube and an odd 4 character code on the bottom bracket? I'd love to figure out the manufacturer.
I wanted to post some pictures, but I'm a new member and am restricted from posting URLs.
03-10-17, 06:35 AM
#2
Senior Member
Join Date: Nov 2004
Posts: 23,223
Mentioned: 656 Post(s)
Tagged: 1 Thread(s)
Quoted: 4722 Post(s)
Likes: 0
Liked 3,040 Times
in
1,878 Posts
Welcome to the forums. That is a very long serial number string. While there were several manufacturers who stamped their serial numbers on the bottom, left hand side of the seat tube, I haven't seen any who have used that particular format. The format itself is more typical of a Taiwanese manufactured frame than a Japanese one. If so, it is most likely to be a contract manufactured frame for a private label brand.
Having a Tange fork on a frame with Ishiwata dropouts is atypical but we do see it occasionally. There should be a date on the steerer tube that will corroborate the format the serial number. The diameter of the seat post will give us a good appreciation of the level of the tubeset used in the main triangle. Also, what, in any, brazed-on fittings does the frame have?
I suspect that the wheels have been replaced, based on the Campagnolo hubs. What are the brands and models of the other major components? You should be able to post a link to a photo hosting site.
Having a Tange fork on a frame with Ishiwata dropouts is atypical but we do see it occasionally. There should be a date on the steerer tube that will corroborate the format the serial number. The diameter of the seat post will give us a good appreciation of the level of the tubeset used in the main triangle. Also, what, in any, brazed-on fittings does the frame have?
I suspect that the wheels have been replaced, based on the Campagnolo hubs. What are the brands and models of the other major components? You should be able to post a link to a photo hosting site.
03-13-17, 01:01 PM
#3
Newbie
Thread Starter
Join Date: Mar 2017
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Front/rear derailleurs are SunTour V-GTluxe.
Bottom bracket, cranks, chainrings and cogs are all Sugino.
Here are some URLs for images:
Frame left/right sides:
1drv.ms/i/s!AoJMA8SZFyVpgdB3EZ3mUH_r4QAi1g
1drv.ms/i/s!AoJMA8SZFyVpgdB7YY1R4dbCqSqVFQ
Rear Derailleur
1drv.ms/i/s!AoJMA8SZFyVpgdEEEht_kE8dr5FaOA
Rear drop:
1drv.ms/i/s!AoJMA8SZFyVpgdB81P638IavuFuDtg
Head tube lugs detail:
1drv.ms/i/s!AoJMA8SZFyVpgdEG1pty6zHE25lKbg
1drv.ms/i/s!AoJMA8SZFyVpgdEFGxLfitxEB_J01g
Bottom Bracket Lugs detail:
1drv.ms/i/s!AoJMA8SZFyVpgdEHYM9TpE3h_qMXUQ
03-13-17, 03:21 PM
#4
Senior Member
Join Date: Nov 2004
Posts: 23,223
Mentioned: 656 Post(s)
Tagged: 1 Thread(s)
Quoted: 4722 Post(s)
Likes: 0
Liked 3,040 Times
in
1,878 Posts
Brazed on cable stops for only the the rear derailleur and rear brake cable is typically indicative of entry level. However, the stamped dropouts are not the typical 2D stamped dropouts but 3D style. This is still entry level but moves the time frame up from boom era, to at least the very late 1970s and possibly 1980s, though still entry level.
The lug set is Eisho Seisakusho's Racer series and the crankset is a Sugino Mighty Tour, though it may not be original. I doubt the forks are original.
Recently, we saw another unidentified frameset that was very similar to this. Same lug set and braze-ons but different dropouts and chrome on the rear stays. Same serial number location but an NW prefix and a much shorter number string. Generally, when there is a double letter prefix, the first corresponds to the manufacturer. The only Asian maenufacturer I'm aware of with a 'D' are Deki and Dodsun. I have no known serial number examples of the former and it's definitely not Dodsun's format. If it is the same manufacturer as the similar frame and the manufacturer is rotating both numbers, that points towards Maruishi or Tsunoda but both typically stamped on the bottom bracket shell and didn't use that long a number string.
My overall impression is an Asian manufactured, entry level frame, from the very late 1970s to very early 1980s. Did you ever determine what diameter seat post is required?
The lug set is Eisho Seisakusho's Racer series and the crankset is a Sugino Mighty Tour, though it may not be original. I doubt the forks are original.
Recently, we saw another unidentified frameset that was very similar to this. Same lug set and braze-ons but different dropouts and chrome on the rear stays. Same serial number location but an NW prefix and a much shorter number string. Generally, when there is a double letter prefix, the first corresponds to the manufacturer. The only Asian maenufacturer I'm aware of with a 'D' are Deki and Dodsun. I have no known serial number examples of the former and it's definitely not Dodsun's format. If it is the same manufacturer as the similar frame and the manufacturer is rotating both numbers, that points towards Maruishi or Tsunoda but both typically stamped on the bottom bracket shell and didn't use that long a number string.
My overall impression is an Asian manufactured, entry level frame, from the very late 1970s to very early 1980s. Did you ever determine what diameter seat post is required?
12-22-23, 03:30 PM
#6
Senior Member
Join Date: Feb 2013
Location: Alta California
Posts: 14,289
Mentioned: 415 Post(s)
Tagged: 1 Thread(s)
Quoted: 3816 Post(s)
Liked 3,353 Times
in
2,187 Posts
Likes For MrGastrognome:
