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Weird seatpost sizing

Bluetree2010-04-28 21:05:33 +0000 #1
Question for you wrenches out there....

My CF frame requires a 31.0mm seatpost. I'd like to get the Thomson Masterpiece but their stock size is 30.9.

Will that .01 variance make any difference of should I be looking for a smaller-diameter seatpost and use a shim?

wolfak2010-04-28 21:19:39 +0000 #2
Ok, just to be clear the difference is 0.1, not 0.01 - a lot larger and will likely make a difference. I think there may be some sort of insert that could help. I'd say go visit your friendly LBS to see what they might know if someone on here doesn't know.
Pedal Wench2010-04-28 21:54:39 +0000 #3
You can try it, but be careful about overtightening to get it to work -- you could crack your frame.

I have a bike that takes an incredibly rare 31.4 post. Even with a shim, some seatposts worked, some didn't. You might get away without needing a shim, because I've seen a great variety within the same sizes.
aicabsolut2010-04-28 21:37:38 +0000 #4
I've seen 31.6 but not 31.0 ...

This was the only shim I could find

Not very helpful.



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