seatpost size help

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Jul 5, 2022
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Pittsburgh, Pa
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I swear I'm losing my marbles, can someone please tell me what size seatpost a huffy rail takes? I know its not 22mm and it doesn't seem to be 20.7mm either. Is it something like 21.15mm? If so, where the heck can I get one!
right, thats my problem though- can't seem to find any 21.1mm seatposts out there. Are they not a very common size or am I just looking in the wrong places?
isn't 13/16" the same as 20,7mm though, which would be too small?
Not much difference between 21.1 and 20.7
21.1 - 20.7 = 0.4 mm
0.4 mm is about 6 times the diameter of a human hair
Maybe 20.7 would work
Worth a try
Can't you measure the ID of the tube? And then shim the 20.7 if it's some weird size close to that.

Or just grab the beer can now and start shimming without measuring since it doesn't really matter at that point. A beer can will likely be just under .1mm thick, so it would only take two layers/wraps to bring the post up to around 21.1 from 20.7
I'm sure all the Huffy Rails used 13/16ths, 20.7mm. Someone may have hammered in a larger size piece of pipe or something. Is the old one slid down inside the frame? I agree with the posters above that a shim is the answer.
tried it, with 2 different seat posts at 20.7, doesn't fit, too small
You can try a shim. Aluminum beer cans are traditional, but soda cans work too.

I visited the Parts Department and found a seat post that measures 21.5mm by 10-1/4" (see pics). I'll PM you with details. Have fun!
seatpost 1.jpg
seatpost 2.jpg