Reviving an old post here, but i think i'll have no choice but to ream my seat post tube if i don't want to go the spacer route.

My bike is a 1987 Schwinn Cimarron MTB, and the Nitto seatpost already there measures 1.045 inches on my quality Starrett dial caliper. That equates out to 26.543mm on a google inch to mm converter,.....not a standard size today.

I've ordered the closest Cane Creek Thudbuster LT suspension seatpost, which i expect to be too tight to use when it arrives. It's supposed to come in measuring 26.8mm

Cane Creek does make one smaller diameter Thudbuster LT seat post that i could have ordered, but i would have had to use a spacer to make up the difference,....not what i wanted to do.

I looked inside my seat post tube on the bike, and it looks like there is paint along all the area i could readily see. I'm expecting that when i pick up a brake cylinder hone i should be ably to remove the paint and primer layer to remove approximately .25mm in thickness needed for a proper fit.

That's not very much, .....and even if a little of that is steel from the tube i'm confident the chromoly frame won't mind!

As i plan to keep the inside of the tube well greased,.....rust formation shouldn't be a problem.

....any thoughts on anything i might be missing?

BTW, if you own a Thudbuster, you might be interested in this idea i have to get proper fitting dust covers fitted to the bushings.

I started a post here on that: http://www.bikeforums.net/showthread...l-Tube-Bushing