Ergotec Seat Post Shim - 25.4mm ID

Customer Reviews (2)
5 / 5| Write your review
£3.99 Please note this product has selling restrictions to your country. was
Manufacturer : 
SJS Cycles part number : 
Manufacturer part number : 
- Material: AL6061-T6
- Colour: Silver
Product Reviews (2)
Questions & Answers (4) Q & A
Download File  
Product Reviews (2)
Overall Product Rating 5 / 5
Excellent product
By Brian Alexander Walker
11 Dec 2020
5 / 5
I recommend this product
Prosgreat fit
After paying Mercian to burn out seized post before respray I can now fit favourite undersized vintage Campag post and with two greased surfaces AND regular maintainance should have no future problems [Top Tip remove/grease Twice a year ]
Repurposing A Seatpost Shim
By Chris Page
20 Aug 2016
5 / 5
I recommend this product
ProsDoes the job for me.
I have a Tortec Explorer seatpost rack. It works perfectly on my old mountain bike with its massive 31.6mm seatpost but recently I bought a 31-year-old Bickerton, on which I want to occasionally fit a rack. The Bickerton has a 25.4mm seatpost and the rack's Q/R clamp won't go that small. This shim (the largest o/d I could find in silver to match the seatpost) solves the problem perfectly. Slide the shim onto the seatpost, slide the seatpost into the seat tube, clamp the rack to the shim, job's a good 'un.
Questions & Answers (4)
Shim for a 26mm seat-post
05 Nov 2023
I have a 26mm seat-post and a 27.2mm seat-post tube. Is the 26.6mm shim (i.e. 1.2mm extra girth) worth trying?
It is not recommended, using an undersized seat post, doing so may result in over stressing the clamp area and cause the frame to fail. SK 06/11/23
What length is the shim?
01 May 2022
Total length is 80mm

JK 03.05.22
Will this work with a Brompton Telescope Seatpost?
28 Apr 2018
Can I put the 26.6 version of this shim in the top of the lower part of a Brompton Telescopic seatpost an then mount a (suspended) 25.4 seatpost instead of the original upper part of the seatpost?

Hi there,

Yes you can, or you can use SJS Cycles part number : 46149 with a 27.2mm upper.

Confirm This Is25.4 Up To 27.8 Please
16 May 2014

The internal diameter of this shim is 25.4, the external diameter is available in lots of different sizes including the 27.8 size you are after. Just select the correct size from the dropdown menu.