USE Seat Post Shim - 30.9 mm ID

Customer Reviews (5)
4.8 / 5| Write your review
£9.99 Please note this product has selling restrictions to your country. was
Manufacturer : 
SJS Cycles part number : 
Manufacturer part number : 
The USE shim system is made to 100mm length, longer than other shims on the market. This gives your seat post much better support inside the frame. Designed with a "top lip" to stop shim sliding into the frame.

30.9mm Inner diameter

31.6mm, 32.4mm or 34.9mm Outer diameter
Product Reviews (5)
Questions & Answers (5) Q & A
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Product Reviews (5)
Overall Product Rating 4.8 / 5
By zsolt szretyko
18 Apr 2021
5 / 5
I recommend this product
Very lightweight and well made alloy shim,just make sure you choose the correct size,and colour, and apply a bit more grease .
Looks good....
By Richard
30 Mar 2018
5 / 5
I recommend this product
Proslonger than most seat post shims
Bought this shim based on other reviews to be able to use an old seat post on my new bike as a spare.....So I haven't used it yet, but it looks like it will do the job!
Brilliant little problem solver!
By Beka
09 Feb 2018
5 / 5
I recommend this product
ProsSimple to use, basically invisible
Just what I needed to make my new dropper post fit my bike. Fantastic fit, nice and secure and no issues with it slipping/not holding even when down hilling on some knarly terrain.
By William O'Connell
16 Dec 2017
5 / 5
I recommend this product
Consbit expensive after postage but ho-hum.
Proseasy to fit, good quality machined alloy
good item. came very carefully packaged to ensure no damage as the walls which are necessarily very thin (30.9 to 31.6). easy to install. needed it for my internally routed dropper post and it does easily cover the full length of the minimum insertion of the dropper. haven't used it in anger yet but the install was a doddle.
It Works
By simon
05 Sep 2016
4 / 5
I recommend this product
Prosaccurate size match
Bit expensive for a thin piece of metal but it makes for a perfect fit of an undersized dropper post.
Questions & Answers (5)
30.9 to 31.6
19 Aug 2019
I have 31.6 seatpost on my frame and i bought 30.9 dropper so which shim i need to buy?
Hi there,

the shim that you would need is the 31.6mm version.

30.8mm to 31.6mm seatpost, do you sell a shim that allows me to use 30.8mm post on my 31.6mm frame
03 Feb 2019
closest one would e.g. product 39557D316
many thanks
I have a Cube with a 31.4mm seatpost and have just bought a 30.9mm dropper post.
18 Sep 2018
Can i get shim cut down from 31.6 to 31.4..!?
Hi there,

Although it is not recommended you could always file it down so it fits, but as we have never tried this we cannot say for certain whether or not it will work I'm afraid.

What size shim will I Need to use a 31.6 dropper post when the seat post on my gt is saying 34.9
05 Dec 2017
My bike is a gt with 34.9 seat post want to ft a 31.6 dropper post. What size shim please?

You will need - SJS Cycles part number : 17628

Hi Can You Confirm If The 30.9Mm Id 34.9Mm Od Shim Is Alloy Or Plastic? Thanks.
05 Jun 2017

The 30.9mm-34.9mm Shim is made from alloy.