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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 03:52 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

  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?

  8. #8
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    Re: Seatpost Metal Shavings; Wrong Size?

    I meant take it to your lbs and try a couple different sizes.

  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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