"Ian G Batten" <[email protected]
> 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
> 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.