# Seatpost clamps - welded vs. non



## JLarkin (Feb 11, 2009)

Two of these frames have welded-on seatpost clamps, one does not.  What is the reason?


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## RMS37 (Feb 11, 2009)

The difference is that the welded collar is earlier. It was used on prewar bikes and early postwar bikes. The removable collar was probably introduced somewhere between late 1946 and the end of 1947.  

Comparing the serial numbers of the two frames to those I have collected so far I would guess that B18160 is from the first or second run of postwar serial numbers and would date to perhaps as early as late 1945 as a first series ?B? or late 1946/ early 1947, if it is a second series ?B?.  (As a first series ?B? it would be the earliest postwar serial number on the list and as a second series ?B? it would be the latest bike I have documented with the welded clamp). 

J50171 CW is a later frame, the CW was added to the serial numbers beginning in about 1948 and the ?J? would lead me to believe that frame is from late 1948.

I believe the seat clamp and the serial numbers are the only significant differences between the two frames and the parts from the later bike should physically interchange without problems. Historically the earlier frame may predate the availability and use of some of the parts of the later bike. 

If you do notice any other differences between the two frames I would be interested in knowing.

Thanks for posting the numbers for the two bikes, every entry brings more information for dating CWC bicycles.

I should also say that I am projecting build times to the best of my ability based on the information I have gathered so far and my estimates may shift or need adjustment as more information becomes available. 

Phil


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## JLarkin (Feb 11, 2009)

> Thanks for posting the numbers for the two bikes, every entry brings more information for dating CWC bicycles.




I did notice one other thing:  the rear axle adjusters did not have any tips on them; they were just flat on the ends.  The boys and the "J" frame have tips on their adjusters.  This could have been an owner modification.  

I'll be using the "B" frame so I guess the girl's bike will become a year older. Since my boys bike has the welded clamp as well with the serial number being C28016, that confirms that it is probably a '47?

Thanks as well for answering and sluething the whole process.  Does my helpfulness get me a discount on that comet tank?


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## RMS37 (Feb 11, 2009)

John, thanks for the response and the ?C? number. I assume that the bike doesn?t have the Cw suffix? I have a picture of that bike from before but had missed the post where you had listed the serial number. This closes the gap between frames with the welded clamp and frames with the removable clamp to between C28016 and D13316 Cw. It also is the current break point for the pre Cw stamped frames if your ?C? bike isn?t so stamped. 

I am still looking for clear documentation in literature showing the time that the welded clamp was introduced, the earliest piece I have so far dates to March 1948. Unless something earlier turns up I would project both the "B" and "C" bikes to be Late 1946 or 1947 production

The other thing to keep in mind is that it is open to speculation if all production shifted to the removable clamp at once or if the two variations were produced along side each other for a period of time.

Regarding adjusting screws, they are another point I haven?t explored or documented but they may ultimately prove helpful for dating production changes in the confusing early postwar period.

And thanks again, I?m getting excited about the in-flow of information about postwar CWC bikes and every data point brings more clarity to the subject.

On the subject of 3-Gill Comet tanks, I still have mine, I?ll PM you later regarding it.

Phil

Here is the patent for the improved, removable seat clamp. It certainly was in use before the patent was filed and interestingly, it was replaced by a self-binding seatpost with no frame clamp by the time it was issued.


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## JLarkin (Feb 11, 2009)

There is a faint impression of a W to the right of the serial number on the boys bike.  I could not see a C around it though.


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## JLarkin (Feb 13, 2009)

One more difference:  The J frame has an externally sprung kickstand, the B frame has an internal-friction Schwinn-style kickstand.  Both are bolt on. The Schwinn style was attached with a bolt and square nut.  The external spring kickstand has a carriage bolt and hex nut.


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## frogger1903 (Feb 13, 2009)

On the topic of Cleveland Welding serial numbers, could anyone help date a J26154  A(W , on a Western Flyer ? The seat post is the type depicted in the above patent drawing. The wheels are Murray, so I assume they have been replaced at some time. Would this bike have had a skiptooth sprocket ? Any help would be greatly appreciated !     Dennis


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## gregv (Feb 20, 2009)

John

any chance of getting an overall shot of the frame on the right? trying to i.d. my frame, and the way that the seat stays meet the seat mast, as well as their shape, look exactly like mine. Also, the lower rear tubes look very very close.

here's the thread on mine if you're interested in having a look:

http://thecabe.com/vbulletin/showthread.php?t=4793

thanks!

gv


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## RMS37 (Feb 20, 2009)

*Here is a quick double answer*,

*Dennis*,

J26154 ACw is at the tail end of the ACw series which I believe followed the AC series and was the first series to use the horizontal slot rear facing dropouts. I have gathered a handful of ACw serial numbers so far and really need more early 50’s serial numbers (especially 53Cw and 54Cw, (and were there 51CW or 52 CW serial numbers?)) to help pin down when this series ended. Using what I have to date it I would place the serial number in 1951. 

Most CWC bikes were set up with 1” pitch until about 1954-1955.

Please post photos of the bike if possible, this will help with serial number to feature correlations.

*Greg V*,

I have followed your posts so far trying to track the manufacturer of your mystery frame.

It is easier to say what it isn’t than what it is, as it has several features that separate it from the standard herd. I can say with surety that it is definitely not a Cleveland Welding or AMF built frame. 

The nature of the undressed welds, the configuration and bend of the down tube and the bends in the seat stays, the unusual extension of the head tube above and below the juncture of the top and down tubes and the exact shape of the drop outs are the features to compare with other bikes to solve the mystery. 

I hate to go out on a limb but based on the above my guess is it may be a Manton and Smith frame. I have been searching my references and I can’t find a M&S with modern forward dropouts but the other features reasonably match M&S features is several photos I have looked at.

Phil


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## gregv (Feb 20, 2009)

Phil

thank-you for the informative reply, which jogged my memory into remembering that Manton-Smith had been mentioned to me when I received the frame as a possible maker; I had forgotten that factoid.

My apologies for any unintentional thread hijacking.

cheers

greg v.


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