Schwinn B9/B10’s

[Jon Olson]

I believe my bicycle is a 1932 26” Schwinn, that I’m restoring it, but for now it’s in parts. Just took the measurement of my rear fender frame. The other pictures are of parts that appear to be original to the bicycle.

 

[RustyHornet]

I believe my bicycle is a 1932 26” Schwinn, that I’m restoring it, but for now it’s in parts. Just took the measurement of my rear fender frame. The other pictures are of parts that appear to be original to the bicycle.View attachment 1409564
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Interesting! If yours is a ‘32 with that serial number, mine was built 3,966 ahead of yours! So it’s appearing older than I thought and still unsure on the wheel size! Thanks for the pictures.

 

[SKPC]

During the 28" to 26" wheel transition period starting in late 1933 through I believe 37, some motobike frame makers (not all) simply used the old 28" frame dimensions for both wheel sizes and some did not, depending on whether the stay width would take a wider 26" tire. Those that did simply used a fender spacer on the seat and chain stay bridges while using a shorter & wider-crowned fork. Early Snyder-made Hawthorne's I know did this a year or so and maybe others . Not sure if Schwinn did so. Colson, in late 33 straight away shortened both the chain-stay AND widened the fork crown/shortened the legs (moto frames) when the 26" size came on the scene. It would be interesting to know when(#'s) Schwinn-made motobike frames and forks began to physically change specific to 26" wheels using the wider fork crowns and wider seat and chain stays. Not necessarily the stay length, which could have remained the same length.

 

[RustyHornet]

During the 28" to 26" wheel transition period starting in 1933 through I believe 37, some motobike frame makers (not all) simply used the old 28" frame dimensions for both wheel sizes and some did not, depending on whether the stay width would take a wider 26" tire. Those that did simply used a fender spacer on the seat and chain stay bridges while using a shorter & wider-crowned fork. Early Snyder-made Hawthorne's I know did this and maybe others . Not sure if Schwinn did so. Colson, in late 33 straight away shortened both the chain-stay AND fork width/length(moto frames) when the 26" size came on the scene. It would be interesting to know when Schwinn made frames and forks specific to 26" with wider fork crowns/shorter lengths and where in the serial number base this ended /began.

Hoping some others chime in with some pictures and measurements so maybe we can put this to rest!

 

[Jon Olson]

After looking up your bicycle I think mine must be a 1933 Schwinn with a 1932 crank. Just like my 1937 Schwinn roadster with a 1936 crank.

And it also measures the same as yours with 26” tires

 

[dasberger]

My '27 frame seems to be around an inch bigger all the way around... Some variation depending where chain adjuster bolts are currently...
Tried to get the tape as close as I could to where you were measuring

 

[RustyHornet]

My '27 frame seems to be around an inch bigger all the way around... Some variation depending where chain adjuster bolts are currently...
Tried to get the tape as close as I could to where you were measuring

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I’m gonna go out on a limb and say based on what we have all concluded here, when the engineers started playing with the idea of 26” tires, they redesigned the frame to accommodate both sometime in the early 30’s and it probably stayed the same for years. I can definitely see a little difference in your ‘27 frame.

 

[RustyHornet]

After looking up your bicycle I think mine must be a 1933 Schwinn with a 1932 crank. Just like my 1937 Schwinn roadster with a 1936 crank.View attachment 1409788
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And it also measures the same as yours with 26” tires

Love your roadster!

 

[SKPC]

See link below to pre-B9/B10 (1933 and earlier)... Early Schwinn serial numbers thread.

Prewar schwinn serial list | All Things Schwinn

Very nice piece! A Superior Racer!?? The serial numbers on the lightweights with the 3 piece cranks only had 4 digits after the letter during that time. And they were hand stamped verses being machine stamped like the lightweights with the one piece crank. Check out @Miq 's thread...

thecabe.com

 

[KingSized HD]

I don't own this but I've been tracking it and have posted it to the "Bikes on Craigslist" forum, looks like the same big cloverleaf sprocket as yours. The ad says it has 28" wheels. The frame size looks smaller than yours to me(at the headtube).

Late 1920s antique Schwinn bicycle - bicycles - by owner - bike sale

Antique Schwinn bicycle model name is electric. This is a big wheel cruiser with 28-in wheels. Morrow rear hub with coaster brake, skip tooth crank, front truss rods, and a nice brass head badge. 19...

medford.craigslist.org