27mm seatposts

[Ian G Batten]

My 2004 Mount Vision has an unbranded seatpost that is
marked 27.0mm. And it presumably is: a 27.2mm seatpost I
have around won't fit, so unless both are mislabelled it's
consistent.

I'd like a more rigid seatpost, as it appears to flex
somewhat if the suspension is locked out. But 27.0mm
seatposts are thin on the ground. Thompson's layback post,
for example, starts at 27.2mm. Any thoughts?

ian

 

[Tony Raven]

Ian G Batten wrote:
> My 2004 Mount Vision has an unbranded seatpost that is
> marked 27.0mm. And it presumably is: a 27.2mm seatpost I
> have around won't fit, so unless both are mislabelled it's
> consistent.
>
> I'd like a more rigid seatpost, as it appears to flex
> somewhat if the suspension is locked out. But 27.0mm
> seatposts are thin on the ground. Thompson's layback post,
> for example, starts at 27.2mm. Any thoughts?
>
> ian

There seem to be quite a few on Wiggle. The Titec is fairly
stiff and a reasonable price. Otherwise there are plenty of
more expensive ones. Several (X-Lite, Use etc) use a shim
system to fit.

Tony

 

[Simon Brooke]

in message <[email protected]>, Ian G Batten
('[email protected]') wrote:

>
> My 2004 Mount Vision has an unbranded seatpost that is
> marked 27.0mm. And it presumably is: a 27.2mm seatpost I
> have around won't fit, so unless both are mislabelled it's
> consistent.
>
> I'd like a more rigid seatpost, as it appears to flex
> somewhat if the suspension is locked out. But 27.0mm
> seatposts are thin on the ground. Thompson's layback post,
> for example, starts at 27.2mm. Any thoughts?

I have a spare Ritchey 27.2 with slight layback which came
on my Cannondale. It's spare because in my opinion it's of
equivalent worth to a fetid pile of steaming dingos
kidneys; the one-bolt design tends to slip when you go down
steep rocky bits leaving you with a saddle pointed God
knows where, which is decidedly uncomfortable. I replaced
it with a BBB two bolt post which was cheap and is very
good - I have a similar (but much larger diameter) BBB post
on my Mantra.

I have to admit I'm surprised at Cannondale and Marin using
such small diameter seatposts because as you say they do
flex. Having said that I'm pleased with my BBBs - they
aren't the lightest things around but I haven't noticed the
flex problem so much.

--
[email protected] (Simon Brooke)
http://www.jasmine.org.uk/~simon/ .::;===r==\ /
/___||___\____ //==\- ||- | /__\( MS Windows IS an operating
environment. //____\__||___|_// \|: C++ IS an object
oriented programming language. \__/ ~~~~~~~~~ \__/ Citroen
2cv6 IS a four door family saloon.

 

[Mark]

Hi Ian, I have on occasion seen a few 27.0mm Campagnolo
Record Aluminum Seatposts show up on ebay. Some of these
are quite sturdy, some have fluted posts, and I doubt if
you would get any flex with these, yet still retain very
light weight.

There is one seller who is in Germany (Cyclo network), who
constantly comes up with stuff like this. Perhaps try a
search? Hope this idea helps, Mark

Ian G Batten <[email protected]> wrote in message news:<ca02n5$vi8$1@news-
out.ftel.co.uk>...
> My 2004 Mount Vision has an unbranded seatpost that is
> marked 27.0mm. And it presumably is: a 27.2mm seatpost I
> have around won't fit, so unless both are mislabelled it's
> consistent.
>
> I'd like a more rigid seatpost, as it appears to flex
> somewhat if the suspension is locked out. But 27.0mm
> seatposts are thin on the ground. Thompson's layback post,
> for example, starts at 27.2mm. Any thoughts?
>
> ian

 

[Phil Brown]

>Hi Ian, I have on occasion seen a few 27.0mm Campagnolo
>Record Aluminum Seatposts show up on ebay. Some of these
>are quite sturdy, some have fluted posts, and I doubt if
>you would get any flex with these, yet still retain very
>light weight.
>
>There is one seller who is in Germany (Cyclo network), who
>constantly comes up with stuff like this. Perhaps try a
>search? Hope this idea helps, Mark

Your LBS can get 27.0 Campy posts from Euro Asia. There have
been problems with cyclo network delivering items wom on
ebay. Phil Brown

 

[Dan Baker]

Ian G Batten <[email protected]> wrote in message news:<[email protected]>...
> My 2004 Mount Vision has an unbranded seatpost that is
> marked 27.0mm. And it presumably is: a 27.2mm seatpost I
> have around won't fit,
---------------

If you want to try using the 27.2 you have.... .2mm isn't
"too" hard to remove with some sandpaper and elbow grease.
Takes a while, and you'll get nasty black Al everywhere, but
its possible.

d

 

[Sdmike]

"Ian G Batten" <[email protected]> wrote in message
news:[email protected]...
>
> My 2004 Mount Vision has an unbranded seatpost that is
> marked 27.0mm. And it presumably is: a 27.2mm seatpost I
> have around won't fit, so unless both are mislabelled it's
> consistent.
>
> I'd like a more rigid seatpost, as it appears to flex
> somewhat if the suspension is locked out. But 27.0mm
> seatposts are thin on the ground. Thompson's layback post,
> for example, starts at 27.2mm. Any thoughts?
>
> ian

Have you checked ebay?

I have a 27.0mm Superbe Pro seatpost. I know if I have one,
they had to make more... Check for XC Pro too. Same basic
SP, just longer.

M

 

[Sergio Servadio]

If I were to need one, not finding a scrap one I would do
this. I would take a Campagnolo two-bolt 27.2mm post and
reduce it to 27.0. No need to have a lathe. A belt sander is
enough, and quite appropriate.

Also, it can be done by a metal polishing shop. Here, the
inconvenience is that the seatpost gets very hot when being
polished; due to thermal expansion of the aluminum alloy, it
is not so easy to confidently measure the diameter while
doing the job.

Sergio Pisa

 

[Matt O'Toole]

Ian G Batten wrote:

> My 2004 Mount Vision has an unbranded seatpost that is
> marked 27.0mm. And it presumably is: a 27.2mm seatpost I
> have around won't fit, so unless both are mislabelled it's
> consistent.
>
> I'd like a more rigid seatpost, as it appears to flex
> somewhat if the suspension is locked out. But 27.0mm
> seatposts are thin on the ground. Thompson's layback post,
> for example, starts at 27.2mm. Any thoughts?

27. was a common size for mountain bikes in the early 90s.
I'm pretty sure that's what my Diamond Back had, and
they made tons of those. So there's bound to be a
healthy supply of these posts somewhere. You might try
Hokie Spokes here in Blacksburg -- they have a whole
wall of bins with nothing but seatposts. Tell Dave I
sent you -- www.hokiespokes.com for the phone number.

Matt O.

 

[Philip Taylor]

Matt O'Toole wrote:

> Ian G Batten wrote:
>
>
>>My 2004 Mount Vision has an unbranded seatpost that is
>>marked 27.0mm. And it presumably is: a 27.2mm seatpost I
>>have around won't fit, so unless both are mislabelled it's
>>consistent.
>>
>>I'd like a more rigid seatpost, as it appears to flex
>>somewhat if the suspension is locked out. But 27.0mm
>>seatposts are thin on the ground. Thompson's layback post,
>>for example, starts at 27.2mm. Any thoughts?

Google can find 'em : http://tinyurl.com/34hvk

** Phil.

 

[James Thomson]

"Ian G Batten" <[email protected]> wrote:

> I'd like a more rigid seatpost, as it appears to flex
> somewhat if the suspension is locked out. But 27.0mm
> seatposts are thin on the ground.

Perhaps not quite as common as 27.2, but certainly among the
most common sizes.

> Thompson's

Thomson's

> layback post, for example, starts at 27.2mm. Any thoughts?

If you really find flex a problem, bear in mind that the
materials used in most of the posts on the market have about
the same specific stiffness, are simple cylindrical plain-
gauge extrusions, and can only therefore be stiffer than
your OEM post if they're also heavier. Expensive posts using
stronger alloys generally do so in order to allow thinner
tube walls to be used, reducing weight, but also reducing
stiffness unless the weight is redistributed to the areas of
greatest stress. Thomson and Ritchey use an oval bore,
increasing fore-aft stiffness at a given weight. A Ritchey
Comp is quite cheap, as stiff as anything else you can buy,
has a little layback, and is widely available in the UK. The
KAlloy model, made in the same factory, is a little heavier,
cheaper, but just as stiff.

You might keep an eye on eBay for an old steel Shimano XT or
DX post - there's an unused one on eBay.de right now [item
3680550946]. It never hurts to ask if the seller will ship
to the UK.

Using a shimmed post would be a waste of money, as reducing
the diameter is a great way to reduce stiffness unless the
tube walls are also beefed up out of proportion.

Having said all that, I'm heavy, and my two hardtails both
use long 27.0mm posts (a light Syncros, and a Ritchey Comp).
I wonder how much your seatpost can really be flexing unless
your rear end is also taking more of a battering than is
good for it.

James Thomson

 

[James Thomson]

"Matt O'Toole" <[email protected]> wrote:

> 27. was a common size for mountain bikes in the early 90s.

It continued to be a common size for steel mountain bikes
with 28.6mm seat tubes while steel mountain bikes
remained common. Most steel Konas, for example, many
steel Marins, the earlier steel Stumpjumpers and
Rockhoppers. It's still one of the most widely available
sizes, though not as common as
27.2

> So there's bound to be a healthy supply of these posts
> somewhere. You might try Hokie Spokes here in Blacksburg
> -- they have a whole wall of bins with nothing but
> seatposts.

and Phil Brown had written:

> Your LBS can get 27.0 Campy posts from Euro Asia

The uk.rec.cycling crosspost, Ian's EU e-mail address and
British ISP suggests that a North American dealer may not be
the most convenient.

James Thomson

 

[Douglas Landau]

Ian G Batten <[email protected]> wrote in message news:<[email protected]>...
> My 2004 Mount Vision has an unbranded seatpost that is
> marked 27.0mm. And it presumably is: a 27.2mm seatpost I
> have around won't fit, so unless both are mislabelled it's
> consistent.
>
> I'd like a more rigid seatpost, as it appears to flex
> somewhat if the suspension is locked out. But 27.0mm
> seatposts are thin on the ground. Thompson's layback post,
> for example, starts at 27.2mm. Any thoughts?
>
> ian

I got one here last month for $10:

http://www.theped.com/blowout.htm right side, almost all the
way to the bottom:

>27.2 Ritchey road seat post $14.95 fits M2 and A1 road and
> many other high quality frames, 250mm, silver. OEM
> (Original Equipment for Manufacturers)

It says 27.2 but they have many sizes including 26.8 and
27.0 in silver and black.

-Doug