Shim for seatpost

[bouddha]

Need a SHIM. for my seatpost .
Would you share with me your experience ? And Give me advice on the best model to choose ?
Thx .

[David Kirk]

What size is the seat tube and what size post do you need to fit in there?

dave

[sjbraun]

I use the USE seatpost shim to run a 27.2mm seatpost in my Pegoretti sized for a 29.4mm seatpost.
Absolutely no slippage in over 5 years of use.

http://www.chainreactioncycles.com/us/en/use-thermoplastic-shim/rp-prod43707

-Steve

[bouddha]

What size is the seat tube and what size post do you need to fit in there?

dave

Size Post 27.2 for a 31.6 seat tube .

[Black Dog]

Size Post 27.2 for a 31.6 seat tube .

Cane creek makes a very good shim for this application for ~$10. I have used one for years and zero problems. A shim is not science rockets.

http://mediacdn.shopatron.com/media/mfg/1739/product_image/7f773e16745a9702bf95a28ad1b7c712.jpg?1241033052

[bouddha]

The best ? Alumunium and Plastic ?

[bouddha]

And looking for a very light model !

[David Kirk]

And looking for a very light model !


I would not use a plastic one and the weight is immaterial.......it will be a handful of grams anyway you cut it and your empty water bottle will weigh a good bit more.

Get an alloy one and you'll be just fine.

dave

[Lionel]

So many 31.6 post why use a shim. Shim sucks.

[bouddha]

I would not use a plastic one and the weight is immaterial.......it will be a handful of grams anyway you cut it and your empty water bottle will weigh a good bit more.

Get an alloy one and you'll be just fine.

dave

Thanks for your advice Dave!
So Go for an Alloy model with USE XCR or Wheels Manufacturing .

[bouddha]

So many 31.6 post why use a shim. Shim sucks.

The choice of a 27.2 diameter instead of 31, 6 is motivated by a slight gain in comfort.

[R2D2]

The choice of a 27.2 diameter instead of 31, 6 is motivated by a slight gain in comfort.

How so?

[Dazza]

The choice of a 27.2 diameter instead of 31, 6 is motivated by a slight gain in comfort.

Me thinks, use the correct size direct fitting seat post
and perhaps 5psi less in the tyres which will make a much greater difference.
If you are not yet, then use bigger bag tyres for lower rolling resistance on the uncomfortable rough stuff (Jan is correct, but he did not discover this, it has always been known)
For a roadie use 25 or 28 mm bag light tyres (English spelling)
This will make a greater difference than a perceived difference in the flex of a 27.2 post compared to 31.6 diameter post.

[UberBike]

So many 31.6 post why use a shim. Shim sucks.

because the frame takes a 29.4 ?

[bouddha]

How so?

Why a 27.2 diameter ?
Because I want to use this model of Specialized COBL GOBL-R seatpost on my frame and see the potential benefit it can bring in terms of comfort.

http://www.labicicletta.com/components/seatposts/specialized-cobl-gobl-r-seatpost.html

[R2D2]

Why a 27.2 diameter ?
Because I want to use this model of Specialized COBL GOBL-R seatpost on my frame and see the potential benefit it can bring in terms of comfort.

http://www.labicicletta.com/components/seatposts/specialized-cobl-gobl-r-seatpost.html

I see.
Don't rule out the Can Creek Thud Buster. It comes in various diameters. And may be more readily available.
http://www.thudbuster.com/products.html

[oldpotatoe]

Why a 27.2 diameter ?
Because I want to use this model of Specialized COBL GOBL-R seatpost on my frame and see the potential benefit it can bring in terms of comfort.

http://www.labicicletta.com/components/seatposts/specialized-cobl-gobl-r-seatpost.html

Oh dear.....just take 5psi outta your tires, use 25c...

Anything else, yikes that thing is hideous.

And 'only' $270..... Yeegads

[BirkWinn]

I too use a shim in my Pegoretti which I didn't want to at first, but after speaking with my shop owner who owns the same frame and use a shim and reading the post on the forum I decided to go with one and it works perfect and I was able to use my seatpost of choice Enve 27.2. I wouldn't use plastic, my metal one weighs pretty much nothing and doesn't hurt your frame or seatpost and can hardly be seen

[bouddha]

Oh dear.....just take 5psi outta your tires, use 25c...

Anything else, yikes that thing is hideous.

And 'only' $270..... Yeegads

I already use Veloflex 25 C.
And these tires need fairly high PSI.

[oldpotatoe]

I already use Veloflex 25 C.
And these tires need fairly high PSI.


Not really, I use Vittoria and use about 85-90 psi and I'm a tenth of a ton. Velo flex no different, cotton 320 tpi clinchers.

[bouddha]

I too use a shim in my Pegoretti which I didn't want to at first, but after speaking with my shop owner who owns the same frame and use a shim and reading the post on the forum I decided to go with one and it works perfect and I was able to use my seatpost of choice Enve 27.2. I wouldn't use plastic, my metal one weighs pretty much nothing and doesn't hurt your frame or seatpost and can hardly be seen

Which metal model did you choose ? Use XCR ?

[dave thompson]

Which metal model did you choose ? Use XCR ?

IMO opinion you're overthinking this. The reason for wanting a 27.2 seat post should be the wide availability of the seat posts. Seat post "comfort" is near nil.

Any good alu seat post shim will work perfectly for you. I used a Problem Solvers shim on my Peg.

[BirkWinn]

Which metal model did you choose ? Use XCR ?

I just called my shop and they weren't a 100% sure but they thought is was either a Nitto or a wheels Works, and aluminum. I my be buying the cane creek black one that was posted earlier since the one I have is silver.

[jemoryl]

I have a Basso Reef frame which takes a 30.0 mm seatpost. When I was first building the bike, I couldn't find a 30.0 mm post but had a nice 29.4 mm one available. A visit to a hobby shop yielded a thin sheet of brass which was exactly the thickness needed to shim the post. At the time, I thought this would be a temporary fix, but it has worked so well, that a 30.0 mm Thompson post I subsequently bought still sits in my closet.