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  1. #1
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    Seatpost Metal Shavings; Wrong Size?

    So I'm building up an old frame which didn't have a seatpost when I got it. A 26.0mm seatpost fits but needs a lot of zig-zagging and some coaxing back and forth to work its way down. Is that too tight, and should I step down to a 25.8mm?
    Last edited by Jonmustang; 02-12-2013 at 02:52 PM.

  2. #2
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    Seems like a kind of easy question -- any thoughts??

  3. #3
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    Re: Seatpost Metal Shavings; Wrong Size?

    Have you ever needed zig-zag coaxing to get other seatposts in while creating metal shavings?

    You should probably try out a few and go with a snug post but not one that's so snug its shaving away metal
    There's something about those long grueling climbs that gets my front end all stiff... And I'm not talking about lockout...

  4. #4
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    Quote Originally Posted by Jonmustang View Post
    So I'm building up an old frame which didn't have a seatpost when I got it. A 26.0mm seatpost fits but needs a lot of zig-zagging and some coaxing back and forth to work its way down. Is that too tight, and should I step down to a 25.8mm?
    A pair of calipers or some internet research will help you find out what size the tube currently is. If you're shaving metal I would suspect it's a bit too tight, but you never know. You could possibly hit it with a ball honer and smooth things out.
    Don't you hate it when a sentence doesn't end the way you think it octopus?

  5. #5
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    Quote Originally Posted by zebrahum View Post
    A pair of calipers or some internet research will help you find out what size the tube currently is. If you're shaving metal I would suspect it's a bit too tight, but you never know. You could possibly hit it with a ball honer and smooth things out.
    Yea, the seat-tube measured an I.D. of 25mm... however a LBS had a little seatpost tube gauge thingy that drops down into the tube, and that one came out "just about 26.0mm", to quote the mechanic. So that's why I tried the 26.0 despite roughing up the post a little teeny bit. Didn't manhandle it, just let it go down snug.

    I can't remember how I.D and O.D. between posts and tubes is matched... if anyone wants to save me a few minutes of Googling, please shout it out!

  6. #6
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    BTW, the reason I wouldn't just go try a couple different sizes is that this is a cheapskate bike build and I'm trying to go with used parts; thus, I don't wanna have to track down and pay for a used part just to have it be slightly wrong when I get home.

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    Quote Originally Posted by Jonmustang View Post
    BTW, the reason I wouldn't just go try a couple different sizes is that this is a cheapskate bike build and I'm trying to go with used parts; thus, I don't wanna have to track down and pay for a used part just to have it be slightly wrong when I get home.
    Kalloy seatposts are something like $15 new retail price. But the difference between 26 and 25mm is huge as far as seatposts go. Maybe hone it a bit?
    Don't you hate it when a sentence doesn't end the way you think it octopus?

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    Re: Seatpost Metal Shavings; Wrong Size?

    I meant take it to your lbs and try a couple different sizes.
    There's something about those long grueling climbs that gets my front end all stiff... And I'm not talking about lockout...

  9. #9
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    Find someone with a ball hone and hone the seat tube. Sometimes seatposts are a tight fit even on brand new bikes. Sounds like 26.0mm fits, this would get rid of the zig-zagging issue.

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