When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Prewar Hawthorne Chain Tensioner Help

-

jlively970

Finally riding a big boys bike
Hello, I am looking for the correct diameter chain tensioners for my ladies prewar Hawthorne ballon tire bike - the ones that came with the bike were completely roached. I tried the NOS CWC chain tensioners in pics on the right and they are just slightly too big in diameter. You can see in the first caliper pic the OG measured 0.2115” and the NOS ones measure 0.2415”. I’m an unsure of the thread pitch also... Lastly, I’m not sure if the OG ones had nipples on the the end of the bolt or not... any help, knowledge, info, or parts would be greatly appreciated. It’d be good to get the lady back on the road!

Thanks in advance

E22CA742-53DD-4D69-AE91-D89704CC1B0F.jpeg


080F0064-933D-4A9C-8DF4-A86C51B7CCB2.jpeg


04E63BD8-FD89-45EC-8B1B-681A646DF7C6.jpeg


63E26D06-7BA9-4084-86A8-50BC18060E45.jpeg


4AA519A3-E431-4685-8B33-21EA94AE82B0.jpeg


B65D91FB-4D47-4799-9706-5BAA65D0072C.jpeg


7AB40CCC-7E1F-4A81-AC10-DECC1AB51124.jpeg


A7812B89-F7CD-4E9B-A1D8-0AEAC511C441.jpeg


C10BA4E4-0942-4EBE-B2C5-02D6AB00D1AE.jpeg
 
the two fatter ones you have, with the nuts on them, are from a pre war Westfield built Elgin, or similar Westfield built machine.

The narrower dimension that came off of your Hawthorne, looks similar to post war Huffman, which had the nipple on them originally.

I had a similar problem trying to use CWC tension screws on a Huffman, they were just a bit wider and stripped out.

Good luck.
 
I believe that the 0.21875" equals 7/32" or about #12-24.
1/4" = .25" might be too big, and #10 = 0.1875" (e.g., Colson) might be too small.
Chain Adjusters.jpg

Hope this helps.
Huffman 12-24.JPG

Huffman also used a square nut, (with mating threads), inside the frame slot - I believe that the frame might not be threaded, and may act more like a guide, the square nut is the fastener opposing the forces on the axle. So a 1/4" might just force-fit in the frame, but a small enough nut that also fits may be hard to find.
 
Last edited:
I believe that the 0.21875" equals 7/32" or about #12-24.
1/4" = .25" might be too big, and #10 = 0.1875" (e.g., Colson) might be too small.
View attachment 1062741
Hope this helps.
View attachment 1062776
Huffman also used a square nut, (with mating threads), inside the frame slot - I believe that the frame might not be threaded, and may act more like a guide, the square nut is the fastener opposing the forces on the axle. So a 1/4" might just force-fit in the frame, but a small enough nut that also fits may be hard to find.
@Mercian
 
the two fatter ones you have, with the nuts on them, are from a pre war Westfield built Elgin, or similar Westfield built machine.

The narrower dimension that came off of your Hawthorne, looks similar to post war Huffman, which had the nipple on them originally.

I had a similar problem trying to use CWC tension screws on a Huffman, they were just a bit wider and stripped out.

Good luck.
Great information and thanks a lot, now I know what I’m looking for!
 
I believe that the 0.21875" equals 7/32" or about #12-24.
1/4" = .25" might be too big, and #10 = 0.1875" (e.g., Colson) might be too small.
View attachment 1062741
Hope this helps.
View attachment 1062776
Huffman also used a square nut, (with mating threads), inside the frame slot - I believe that the frame might not be threaded, and may act more like a guide, the square nut is the fastener opposing the forces on the axle. So a 1/4" might just force-fit in the frame, but a small enough nut that also fits may be hard to find.
This is really great information, where did you find that data on the screw chain adjusters? Thank you
 
Back
Top