Originally Posted by
cannonride15
No shim per say, the seat tube in vicinity of post clamp and juncture with top tube measures 26.4mm; below clamp area seat tube measures 28.4mm. this seems to jive with Jody Lee's observation of straight walled Carbolite 103 tube thickness of 1.2mm, as noted on his site.
Thanks for the measurement on that. My seat tube is a consistent 28.2/28.3mm (depending on where around the circumference I measure the diameter). Your observations are consistent with the comment from @
francophile regarding a "necking" of the seat tube up near the clamp. As far as I can get my caliper up against the lug there, I can't get less than 28.2mm. And that
does explain my 25.8mm seat post. 28.2 - 2*1.2 = 25.8 on the nose.