I have an older schwinn roadbike frame that looks like its from the 70's or maybe the 80's. The serial number is on the bottom of the bottom bracket sideways. I checked schwinn serial number websites and apparently my bike frame doesn't exist because it starts with an I. My serial number is I702756. Before I had it powdercoated it was like a maroonish brown and yellow. Please help me figure out what frame this is.
Vintage Schwinns, Classy Cannondales, & an '83 Santana Tandem
Welcome to C&V.
Pictures and a list of the original components will be the only way for us to help you. Does it still have the round headbadge? If so, look for a small 4 digit number stamped in the badge. The first digit will tell us the year in either the '70s or '80s. Pictures of the lugs, seatpost collar, and rear dropouts are the most helpful along with the entire bike and the components. The "I" could be a badly stamped J or L.
No "I"s (or "O's) were ever used in Schwinn SNs, I don't think, due to their similarity to 1 and 0.
All the Schwinn SNs with which I'm familiar are on the head tube (or head badge) or on the right drop out. So I'm thinking that what you're looking at is a part ID number. Look in the other spots and see if you find anything.
If that is a Serial Number, it could be a Japanese-made frame--then the letter could be J or L, as Pastor Bob says. In that case, J=September and L=November, and the second digit would be the last digit of the year (in the 1970s, I presume). That would make your bike 1977. Edit: According to a post on the Schwinn Forums by Scooper from 2006.
I think that some bikes before the 1960s had SNs elsewhere, but I'm not for sure. Edit: 1951 and before, according to "bunchobikes"--but weren't those mostly middleweight and heavyweight, with ashtabula crank?
I have an early 80s Japanese Schwinn, and it's SN, if I recall, is on the dropout.
Good quality, closeup pics of the frame (i.e., lugs, dropouts, etc.) and of the original components, if any, would help a lot.
Last edited by Roll-Monroe-Co; 04-16-08 at 03:17 PM.
Reason: New research results
OHHHH, the Greenville-built Schwinns. Well, yes, of course they're different!
Er, actually, if they are, I didn't know that.
Oh, but of course, for me, Schwinn time ends in 1980, since the SLDB ends in 1980.
So, what's the formula for post 1980 Schwinn SNs, and what year does it stop being reliable?
At least as far as the Schwinn le tour models go, the serial numbers weren't on the bottom bracket shell until 1984; my 1983 has the serial number on the dropout, but the '84 has it on bb shell.
As far as '80's Schwinns having serial numbers that are reliable, I'm not sure many of them do, at least not the Greenville ones. The Greenville-built Schwinns often have serial numbers starting with "S" (which might indicate Greenville), then a letter representing month of manufacture, then a number representing year of manufacture. Such as the serial number starting with SG4 I mentioned above, which would seem to indicate Greenville, July, 1984. But we've discussed a bunch of these Greenville-built Schwinns here, and there are inconsistencies.
There is also the anomoly with Bridgestone using place holders for months prior to the model year (for example, November and December of 1982 for the '83 model year would be X3 and Y3, then January would be A3), but this probably started after this Bulletin was published (don't hold me to those years). I think some Panasonic (Japan) built Schwinns also had serials on the headtube (Voyageurs), but that probably came later as well. The '80s dating was crazy! We can't even get a straight answer out of Richard Schwinn.
I'm in the same position as the original poster - I have bike, headbadge says Schwinn Chicago, 4 digit code is 0267, has been repainted, so no decals to look at, has a serial number on the bottom bracket I637212 - and it is definitely an I - see photos of it in this thread Help identifying a bike
Schwinn Traveler 1964, High Sierra 1984, EV Global eBike, Schwinn 1977 LeTour
Originally Posted by Scooper
I have a "project bike" I got and am almost done- now trying to accurately date and get right decal. Atypical S/N on head tube is J1035494 I'd think this was a 1971 except for the 7 numerals instead of 6. It is a 5 speed tandem, I was told it was a twinn, but I'm thinking deluxe twinn now. Will get pix on soo, as I also need to assure rear reflector I got with it is period correct. Thanks!