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seatpost shim???

VeloVT2010-04-29 01:16:58 +0000 #1
My new bike came with a straight post (no setback). I need some setback and at my fitting I was able to purchase a carbon post that was a trade-in (it came on a new bike in the shop and the buyer swapped it out for something different), so it was pretty cheap. However, I hate the tilt adjustment mechanism. It's a one-bolt design, and tilt adjustment is both a little awkward and not infinite (there are grooves in the adjustment cradle). I'd like something with a nicer adjustment mechanism, but I don't want to drop a lot of money on a seatpost right now.

I have a Thomson post from my other bike that is very easy to use, but it's 27.2, and my carbon bike takes a 31.6 diameter post. The guy who fit me mentioned that one could buy seatpost shims that allow the use of smaller diameter posts. Does anyone have experience with this? Are there functional problems with using a shim? Are there aesthetic issues? Does it look strange to have a skinny seatpost on a fatter-tubed frame?

Pedal Wench2010-04-29 01:21:17 +0000 #2
I use a shim on one of my bikes -- it uses a very proprietary 31.4mm seatpost, which is almost impossible to find. Functionally, there's no problem as long as you make sure the shim is fully inserted. Aesthetically, it doesn't look as nice as it would if it were the right size, but at least I can ride that bike now.
motochick2010-04-29 01:22:13 +0000 #3
Liza, I had the same tilt adjust problem with my seatpost and was able to fine tune it with a soda can. Get your tilt so it is just a little nose up from where you would like it to be. Mark it with paint or nail polish so you don't lose the spot. Cut a thin strip of a soda can and wedge the strip in the back of the ratchet area. This will lift the back up so the front end isn't sticking up so high. If you need more lift in the rear, add another strip (or fold a bigger piece in half). My hubby and I have both done this and now we do not need to waste money a another seatpost.




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