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Crank help!

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GUSMC

Look Ma, No Hands!
Hi folks, I recently purchased a 1951 CWC Western Flyer. I had noted a very old and unusual weld joining the right hand pedal to the crank but keen to give it a whirl I took it out for a spin. All went fine until the pedal fell off due to the weld failing. On inspection both the old pedal and the crank have completely stripped threads.
Apart from stripping and rebuiding my Schwinn, I have limited experience of Amercian-style one piece crank systems; so my question is: how universal are they?
Width of bottom bracket = 68mm
Length of crank (centre axle to centre pedal axle) = 7" / 180mm

Being in the UK Im happy to go with the easiest fix for this one and not so concerned with finding a period perfect replacement.
I guess my question is: are there any other measurements I should be looking out for?

Any help appreciated, cheers from Scotland!

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There are only 2 common kinds of those one piece cranks: 1) Schwinn and 2) everything else.

If you put a Schwinn crank in a non-Schwinn (or vice versa), you must change all the parts (cones, cups, bearings, hardware, etc.) but it does fit in the frame. The chainring fits either kind and the so do the pedals.
 
Have you considered taking the crank out of the bike, and perhaps going to a machine shop and having it rethreaded? I had a screw socket on a 1940s electric fan done like that once; it had stripped out. It might cost a bit though, just depends on the machine shop. That might be the easiest option, since it could be a little harder finding just the right crank, plus then, you can still say your bike has the original cranks, and not replacements. The downside is the cost; perhaps between $50 & $100 to have something like that done I would guess. It might also be worth checking an older radiator shop, as places like that may have many of the same capabilities as a machine shop, but a lower prices.
 
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There are only 2 common kinds of those one piece cranks: 1) Schwinn and 2) everything else.

If you put a Schwinn crank in a non-Schwinn (or vice versa), you must change all the parts (cones, cups, bearings, hardware, etc.) but it does fit in the frame. The chainring fits either kind and the so do the pedals.
Ok great thanks - well that's good to know. Makes it a bit easier!
 
Have you considered taking the crank out of the bike, and perhaps going to a machine shop and having it rethreaded? I had a screw socket on a 1940s electric fan done like that once; it had stripped out. It might cost a bit though, just depends on the machine shop. That might be the easiest option, since it could be a little harder finding just the right crank, plus then, you can still say your bike has the original cranks, and not replacements. The downside is the cost; perhaps between $50 & $100 to have something like that done I would guess. It might also be worth checking an older radiator shop, as places like that may have many of the same capabilities as a machine shop, but a lower prices.
I have. I was even considering enlarging to a 9/16" thread and then could probably find easier replacement pedals in the UK (1/2" is not at all common here)
There is a decent engineering machine shop near me on the River Clyde that I have used on occasion. And because they're used to big jobs like making steel girders for bridges or building engines, they have never charged me but ask only for a donation into their charity box, so I might try 'em on Monday. Thanks
 
I have. I was even considering enlarging to a 9/16" thread and then could probably find easier replacement pedals in the UK (1/2" is not at all common here)
There is a decent engineering machine shop near me on the River Clyde that I have used on occasion. And because they're used to big jobs like making steel girders for bridges or building engines, they have never charged me but ask only for a donation into their charity box, so I might try 'em on Monday. Thanks
That sounds like a good idea. When I was a child, I had a small repair similar to this that I needed done by a machine shop once, and when I went there to see how much to have it done, the rate was very reasonable. All it cost me was 2 jars of preserves, and $5 in the collection at church!, I reckon because I was a kid.
 
GUSMC:
I don't know about Scotland, but in the USA one-piece (Ashtabula) cranks are readily available. To follow up on Mr. Bloo's comment, they all fit into threadless bottom brackets with a diameter of 51.3 mm (healthy 2").
Have fun!
1239733
 
GUSMC:
I don't know about Scotland, but in the USA one-piece (Ashtabula) cranks are readily available. To follow up on Mr. Bloo's comment, they all fit into threadless bottom brackets with a diameter of 51.3 mm (healthy 2").
Have fun!
View attachment 1239733
Thanks for the pic and the info! In Scotland one-piece cranks are not really embedded in British bicycle history - with the effect that they are not readily available at all. (From about the age of 8 years old Ive been knocking worn out cotter pins into cranks with a hammer).I went to 5 bike shops yesterday and all told me that one-piece cranks are only found in children's bikes and very cheap adult bikes. Thanks for telling me their proper name. Now I can irritate my local bike shops even further by asking to see their range of Ashtabula cranks.
I'll find one on ebay!
 
GUSMC:
I like your style: irritation by vocabulary. The "very cheap adult bikes" angle might be worth pursuing. The cranks on cheap bikes (e.g. Huffy) usually have crummy chrome, but are serviceable. You may be able to find a used bike for parts (girls bikes are usually cheaper and in better condition).
 
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