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What Model Might This Be?
- Thread starter Trilobite
- Start date
Lightweightbikes
Look Ma, No Hands!
Schwinn corvette from 1955 to 59...the serial number is located on the leftside rear leg to make sure thank you
Tore the bikedown, and ready for powder coating. I will have the rims done, also. I can’t, for the life of me, find a serial number, even after lightly sanding the paint off of the spots where it might be, using a DreMel wire wheel. I’m starting to think the frameset is not vintage at all, but rather, built to replicate one. I don’t know enough about this. The crank appears to have “SH 3-7” cast into it. Does that sound right? Confusing...
Crank looks like SA(?)3(?)78. I would guess that's a Schwinn crank made at Ashtabula Forge in 1978. I see Schwinn's typical red primer on the fork, and a Schwinn VSF crown race. Can you see any trace of old striping on the fork? I can't see enough of the chainwheel to tell if it is a 5 speed one, but from what I can see of it probably not.
The frame sure looks like a real Schwinn Electro-Forged frame to me (but no red primer). I cannot explain the lack of a serial number. The places I would look are 1) under the bottom bracket 2) the rear dropout 3) bottom of the headtube, rider's left side, toward the front. You mentioned looking for the serial. Have you looked in all 3 spots?
It looks like kickstand cam has a closed back. Does anyone remember what years those were used?
I wonder what the width is between the seat stays? Could this be a ballooner frame instead of a middleweight?
The frame sure looks like a real Schwinn Electro-Forged frame to me (but no red primer). I cannot explain the lack of a serial number. The places I would look are 1) under the bottom bracket 2) the rear dropout 3) bottom of the headtube, rider's left side, toward the front. You mentioned looking for the serial. Have you looked in all 3 spots?
It looks like kickstand cam has a closed back. Does anyone remember what years those were used?
I wonder what the width is between the seat stays? Could this be a ballooner frame instead of a middleweight?
GTs58
I'm the Wiz, and nobody beats me!
I'm going to say that might be a 1961 or earlier model. I believe the front chain guard mounting tab was made out of flat stock and then sometime during the 62 production the tab was an L and it was electro-forged, not brazed, to the BB shell. The kickstand looks like it has an added stand repair kit with that end cap in the stand tube. After looking at the left rear dropout is appears someone has sanded down the teeth marks made by the serrated washers. The serial number should be on that left dropout! Use sandpaper to remove the paint. They will be blasting the frame for Powder so the paint has to come off anyway. If the bike is a 60's model and fork is original, there should be a date stamping on the inside of the left fork leg just above the axle slot. Either a two or three number stamping with month and last digit of the year. 8+3 would be August 1963.
This is turning into a real mystery. I’m beyond impressed at the level of expert of the forum members, as well as appreciative of your efforts in trying to “crack the code.” Further exploration with a Drexel Multimax has turned up two stampings on the inner rear dropouts. The left side reads “9113,” while the right side stamping is inverted, reading “1200.”
The fork is a conundrum. Sanding through the red primer yielded nothing where a serial number was reputed to be, but the dropouts themselves appear filed. Were these all so crudely hewn, or has mine been doctored? The only thing I could turn up was an “M” on the inner crown. The crank is cast with “SH 3-78.” It’s definitely been apart/retrofitted, as the grease in the bb shell is fresh and copious. The rims are painted (badly). In fact, the whole shebang was badly painted with a brush. The tires are 26 x 2.125, so a ballooner.
Off it goes to be powder coated on Monday, rims too. Since it rides so well, I’m excited to put it all back together. The tank horn works, but not the cheesy headlight, so I’ll rectify that. Thanks everyone!
The fork is a conundrum. Sanding through the red primer yielded nothing where a serial number was reputed to be, but the dropouts themselves appear filed. Were these all so crudely hewn, or has mine been doctored? The only thing I could turn up was an “M” on the inner crown. The crank is cast with “SH 3-78.” It’s definitely been apart/retrofitted, as the grease in the bb shell is fresh and copious. The rims are painted (badly). In fact, the whole shebang was badly painted with a brush. The tires are 26 x 2.125, so a ballooner.
Off it goes to be powder coated on Monday, rims too. Since it rides so well, I’m excited to put it all back together. The tank horn works, but not the cheesy headlight, so I’ll rectify that. Thanks everyone!
GTs58
I'm the Wiz, and nobody beats me!
Looking at your front fork drop outs it's obvious one of the owners went to town with a grinder and cutting disk on the bike. I'd be tossing that fork in the scrap pile! Those stamped numbers on the rear drop outs are part numbers. So no signs of a SN stamping on the left rear drop out above the slot huh?
As I suspected. No manufacturer I’m aware of would make something so crude. Makes me think a previous owner hogged out the dropouts to get a larger axle to fit. I haven't seen that level of shade tree mechanics since my childhood friend's attempt to turn his Stingray into an extended chopper with sections of plumber's tubing. 
No serial numbers to be found.
No serial numbers to be found.My comment about ballooners had more to do with identifying the frame. When Schwinn started making middleweight frames, they narrowed the frame at the rear. There is supposed to be some way to tell by how many fingers you can get in at the seat stay bridge. I can't remember how many, but it did change for sure. So that is one thing to nail down. Balloon tires and rims will fit the middleweight frame, barely.
Also, Schwinn's middleweight rims (S7, 26x1-3/4") will not take balloon (S2, 26x2.125) or non-Schwinn middleweight (26x1.75") tires. So, if the frame is middleweight, then the balloon rims cannot be original.
Well... maybe one exception. When Schwinn brought Balloon tires back in the late 70s did they widen the frame back out or did they just use the middleweight one? I can't remember.
Another thing about the frame that changed from 58-59 was how high the seatstays are, so I've been told, causing a change in the fenders. Does anyone have the measurements? If it happens to be the later version, and is also 61 or earlier as outlined in GTs58's post, that would narrow it down to 1959-61.
EDIT: I just put my tape on TOP of the chainstay right at the bottom bracket and measured to the TOP of the seatstay right at the back of the seat tube. That is effectively the same as a center-to-center measurement. I measured 16-1/8". Bike is a 61 Speedster (S7 middleweight).
The width available between the seat stays at the bottom of the fender bridge is 2-5/8". Or alternatively measured from center to center on the seatstay tubing at the bottom of the bridge it is 2-15/16".
EDIT 2: The exact spot you should find the serial number on a late 50s early 60s Schwinn if it were there. 61 pictured. The dropout on the left as you are sitting on the bike. But, have you also looked under the bottom bracket? That would imply a much older frame but I would still look.
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Ahh, many thanks for all your assistance. Put a fresh pad on the Multimax and kept sanding. The frame was brush-painted and it was on there quite thick. Finally found the serial number on the left rear outside dropout: “32791.” C to c as per your measurements yielded 16.5 “, and c to t was 18.5.” Measured the rear stays above the bridge at 2.5”. Rim width is 2.75” and the hubs, I believe, are Bendix? Single red stripe on the rear. Would this indicate a middleweight frame with non original rims? Cheers.
