Anyone know seat post size SR Semi-Pro?
#1
GDFTR
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Anyone know seat post size SR Semi-Pro?
I just picked up a 1982 and it is in immaculate condition the paint looks like it’s less than a year old there’s no rust very few chips and scratches. Anyhow it’s got an aftermarket seat post that is a 26.4 and I can tell it’s not the right size because the binder bolt is pinched so much that it’s no longer in a straight line. Hopefully somebody knows what the right size is without me having to just guess and try different sizes. Thanks!
#2
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I have no info other than having owned a few Japanese bikes of that era. All mine were 26.8. ('76 Fuji Pro, ~80 Schwinn sports frame, ~83 Sekine, '83 Miyata 610.)
I am going to guess that seattube will need to be reamed to fit a proper sized post without gouging. Short of reaming, perhaps use a post you don't care about, insert to scratch point, note location and file gently with a large round file and repeat until post goes in cleanly. (Keeping in mind the 2X 4 analogy. You can cut a 2 X 4 shorter, but cutting it longer is VERY difficult.)
I am going to guess that seattube will need to be reamed to fit a proper sized post without gouging. Short of reaming, perhaps use a post you don't care about, insert to scratch point, note location and file gently with a large round file and repeat until post goes in cleanly. (Keeping in mind the 2X 4 analogy. You can cut a 2 X 4 shorter, but cutting it longer is VERY difficult.)
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#5
WGB
I went back and cannot find an exact reference, only photos. Definitely an SR seat post and "I'm sure it was 27.2" but faint possibility that it might have been 27, but still convinced 27.2
If no one who owns one posts on this thread, search the for Semi-Pro threads and ask the original posters to check their seat post diameters....
If no one who owns one posts on this thread, search the for Semi-Pro threads and ask the original posters to check their seat post diameters....
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#6
GDFTR
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Thanks for the quick replies. I do have a 27.0 in an old English Falcon which I can try and if it’s still loose then I know it’s the 27.2
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I would have guessed more like 26.6mm, but only because my Semi-Pro weighs 24 pounds (just like my Miyata 912). The 912 used a very heavy tubeset as described in the recent post of the mid-1980's Bicyclist.

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