Seat Post sizing - '35 Hawthorne
- Thread starter thebigorangecat
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All my 30 - 40s Hawthornes take 5/8 round stock. I have one old bike that has a 3/4 rod. It could also be 13/16 as one of my 30s bikes had that. I would get some various size stock to see what fits. It comes in handy co figuring this out. The hardware store hot rolled rods bend easily so I use either cold rolled or 2024 aluminum.I get a few different measurements as the tube heads down - but was there a standard size for these frames?
I have it somewhere between 3/4" and 1"
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I have some double bar drop frames; I prefer shim-less posts that neck down and bend to the 5/8" for the seat clamp. My Westfield has 13/16". My Colsons have 3/4". Another unknown (Schwinn, Mead?) has a 3/4" post with very-thin (Wald-like) shim and looks like the seat tube may have been over tightened at one time; that one may need work.
I have some later 1940's Snyders, and they have 27/32" (same as 1/2"-IPS pipe O.D.); very odd yet still available. I don't have any bikes (or tricycles) in my limited collection that would take a 5/8" post without a thicker ~1/16" all-around shim.
I have an old Lonn Patent GWM Crown post made from stamped sheet/bar, rolled and welded at a seam; it measures 0.7 to 0.75 depending on where it is measured.
I have some later 1940's Snyders, and they have 27/32" (same as 1/2"-IPS pipe O.D.); very odd yet still available. I don't have any bikes (or tricycles) in my limited collection that would take a 5/8" post without a thicker ~1/16" all-around shim.
I believe the clamp area on some old bikes does not progress all the way down the tube.
I have an old Lonn Patent GWM Crown post made from stamped sheet/bar, rolled and welded at a seam; it measures 0.7 to 0.75 depending on where it is measured.
I am using the same frame in a bike in the "builds"s section. My post measures a weird size:13/16th. These frames were hand made, hand-brazed, and the junction where the seat post inserts is sometimes not smoothed enough on the interior. You may need to ream it a bit then try a 13/16". Too bad about that rapaired down tube.
