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[Closed] What's the inner diameter of a standard 30.9 seatpost?

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I'm hoping it's around 27.2mm?

Those of an inquisitive nature can probably work out why I am asking ๐Ÿ˜‰


 
Posted : 12/05/2012 6:05 pm
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The inner of a seatpost isn't necessarily circular, Thomson are ovalised, for example.


 
Posted : 12/05/2012 6:07 pm
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Depends how much metal there is. It will vary post to post...


 
Posted : 12/05/2012 6:07 pm
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Aye, just want a general idea.

Lets say a bog standard bonty on a trek.


 
Posted : 12/05/2012 6:10 pm
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It'll depend which one. Selects are quite thick, Race Lites aren't. There really is no consistency!


 
Posted : 12/05/2012 6:11 pm
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And thye'll more than likely taper with thinner walls towards the clamp and thicker ones where it's in the frame.


 
Posted : 12/05/2012 6:17 pm
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They vary a lot, I've got 6 and they are all different. I found a couple that take another seat-post internally (I presume that is what you want). One took a 25.4, another took a 27.2, the rest were a bit random.


 
Posted : 12/05/2012 6:21 pm
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Spot on Nick, ta very much!


 
Posted : 12/05/2012 6:23 pm
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If you try and ride a bike setup like this I think you'll regret it ๐Ÿ™


 
Posted : 12/05/2012 6:31 pm
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OK so your 30.9 is seized. Just cut the top off and measure internally.


 
Posted : 12/05/2012 6:48 pm
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Would you be sticking a small pump up there, or an emergency sausage roll?


 
Posted : 12/05/2012 7:37 pm
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Ya'll almost got it.

Aquired a hack/pub bike frame. Has a 27.2seat post stuck in it. Too tall for me. Tried a number of the normal ways to get it out. Failed. Cut off part of it, slide 31.6 over the top, clamp on with seat clamp. Sorted.

Sourced a 31.6 that is roughly 27.5 internally. Looks like I'm sorted ๐Ÿ™‚


 
Posted : 12/05/2012 8:12 pm
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You will die horribly with the shattered remains of two seatposts up your fundamental.

Either that or the a&e staff who remove them won't believe how they got there.


 
Posted : 12/05/2012 8:15 pm
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fingers crossed =]


 
Posted : 12/05/2012 8:19 pm
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I'd be clenching, if I were you ๐Ÿ˜‰


 
Posted : 12/05/2012 8:20 pm
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Huh? How are you gonna clamp it?


 
Posted : 12/05/2012 8:27 pm
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Magic!


 
Posted : 12/05/2012 8:41 pm
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How's the butt?


 
Posted : 13/05/2012 6:09 pm
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๐Ÿ˜ฏ


 
Posted : 13/05/2012 6:10 pm
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cant you knock it into the frame


 
Posted : 13/05/2012 8:18 pm
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I've run a bike with two seat posts, I had to go into a bike shop and have them try a few to get one the right size. I cut the head off the larger one and then cut a slot so it would clamp up, like I imagine you're going to do.

I didn't die.


 
Posted : 13/05/2012 9:31 pm