Seat post shim - As...
 

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[Closed] Seat post shim - Asking for trouble?

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Topic starter
 

Never had a shim before, are they to be avoided if possible?

Ordered a cheap Crank Brothers dropper but failed to notice it's 30.9. Bike is 31.6, damn it!

Shim (100mm) can be had for £10 ish. Will be a 170mm drop post with probably another 30mm extra post out of frame so a fair length.

Can replace for a brand X for another £40 in the correct size.


 
Posted : 22/05/2020 10:33 am
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I ran 30.9 dropper in 31.6(shimmed) no issue


 
Posted : 22/05/2020 10:50 am
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Used them for years, in various configurations. Zero problems.


 
Posted : 22/05/2020 11:10 am
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You'd be surprised at how many frames come shimmed already.


 
Posted : 22/05/2020 11:12 am
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Ran a 30.9 dropper post in a 31.6 frame shimmed for a while, used carbon grip to make sure i didn't need to torque it up to tight just in case that affected the dropper working but never had any issues


 
Posted : 22/05/2020 11:15 am
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Shim shimmy it is. Cheers guys. Should probably be more worried about the Crank Brothers post.


 
Posted : 22/05/2020 11:38 am
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Been running a Cane Creek shim for years, just does what it's supposed to, zero drama. It's supposedly a good quality one though, with a good texture to it to about slippage. I guess that makes a difference.

Having a plastic bushing in between the seat tube and seatpost is not as weird as mountain bikers often think. Loads of mechanical equipment always have a polymer bushing of some sort in similar assemblies


 
Posted : 22/05/2020 2:08 pm
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USE shim will do the job.


 
Posted : 22/05/2020 9:57 pm
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As above shims in use at least 30 years.

To note though is that you can get slippage, especially with the USE nylon ones. Which might promote you over tightening, and I dont know if that would damage the mechanism of the post, but I dont think it would do it too much good. Possibly deform it to prevent it from working.


 
Posted : 23/05/2020 1:41 am

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