27mm seatpost in 27...
 

[Closed] 27mm seatpost in 27.2mm frame?

Posts: 4787
Full Member
Topic starter
 

I've not tried it yet but I don't think there's enough 'bend' in the seat tube for it to tighten enough.
Think Ive read on here ages ago about 'coke can shim', does it work?
Did also thick about wrapping duck tape around the post but would that start to unwrap etc?
It's a new old stock USE suspension post that I want to use in my new hybrid/commute ebike so once got the correct height set it won't be moved much.
Cheers.


 
Posted : 04/11/2021 4:09 pm
Posts: 377
Free Member
 

Deffo use coke can over duck tape.


 
Posted : 04/11/2021 4:18 pm
Posts: 5909
Free Member
 

Coke can will be perfect. Slather lots of grease on to avoid corrosion, and leave a bit poking out with a tiny lip bent in - you don't want to lose it down the seattube.


 
Posted : 04/11/2021 4:22 pm
 LAT
Posts: 2394
Free Member
 

why buy a shim? they are pretty cheap and will work without any hassle.


 
Posted : 04/11/2021 4:45 pm
Posts: 9057
Free Member
 

I've used an old drink can and it's fine.


 
Posted : 04/11/2021 5:12 pm
Posts: 5909
Free Member
 

@LAT Not sure you can actually buy a shim to take a 27.0mm post to 27.2mm...?


 
Posted : 04/11/2021 5:17 pm
Posts: 2320
Free Member
 

Don't do it without a shim the frame will crack

Use a coke can as above, coke can alloy is 0.1mm thick so perfect

I did it to take a 30.0 post to 30.2, was a little tight but worked. You could wet and dry the paint off it.

Just use a bit thats about 10cm long to make a nice shim and get plenty of support down the tube.


 
Posted : 04/11/2021 5:51 pm
Posts: 4787
Full Member
Topic starter
 

Cheers, need to buy a can then...
Will special brew do? 🙂


 
Posted : 04/11/2021 6:10 pm
Posts: 3358
Free Member
 

+1 for coke can shims, used to have to do it all the time with BMXs and early MTBs.


 
Posted : 04/11/2021 8:46 pm
Posts: 801
Full Member
 

Is the 27mm seat post special? Is it a nice frame?

I guess it’s not the point if you are asking but if If the post is nothing special and the frame is at all nice… 27.2 seat posts aren’t expensive and will save faff and risk to frame, fingers, knees and aesthetics.


 
Posted : 05/11/2021 9:10 am
Posts: 2006
Free Member
 

Coke cans are a lot flimsier than they were and have a non stick coating

You can buy small bits of metal sheet used by railway modellers on fleabay to get something in steel for not a lot


 
Posted : 05/11/2021 11:40 am
Posts: 12860
Free Member
 

Coke can is absolutely fine 0.1mm is 0.1mm put the inside on the outside and as someone suggested above roll the end over a bit to stop it sliding down as you put the post in.

I put it in once unrolled and with a pick, run round between the post and the shim to start it rolling.


 
Posted : 05/11/2021 12:09 pm
Posts: 2320
Free Member
 

Will special brew do? 🙂

As long you don't contemplate drinking it first.


 
Posted : 05/11/2021 4:23 pm
 Bez
Posts: 7438
Full Member
 

Special Brew is actually a great choice because it comes in taller cans, so you get a longer shim… (for those wanting a longer shim without having to buy tramp fuel, I’ve tended to use cans of Waitrose tonic water 🙂)


 
Posted : 05/11/2021 6:37 pm
Posts: 4787
Full Member
Topic starter
 

LOL, not drunk special brew since the 80s but yes I was thinking it's a taller can so will find an easier to drink taller can alternative, maybe tonic water, maybe not!


 
Posted : 06/11/2021 5:57 pm
Posts: 0
Free Member
 

Surely its Monster energy or Redbull, or has sponsorship of bike events subconsciously worked on me.


 
Posted : 06/11/2021 6:34 pm
Posts: 24436
Full Member
 

Waitrose tonic water

peak STW


 
Posted : 06/11/2021 7:43 pm