Seatpost Problem, 26.8 vs 26.6, did I damage anything
 

I recently purchased a new (nothing fancy Kalloy) seat post to accommodate a low profile saddle. I took measurements with my dial calipers, looked it up on Sheldon Brown's database, and most importantly looked at the previous seat post (although there was some rust by the size engraving), and everything pointed to 26.8mm.

I went to install it, deburred the frame, used a ton of grease, and it was nearly impossible to get in. I ended up sanding some material off the seat post and then with turning motions (using the saddle for leverage) was finally able to get the seat post in (albeit maybe a few mm higher than I want it). I gave up trying to adjust it any more.

Now, on longer rides I'm getting a little pain in the elbows, and I attribute this to the slightly higher saddle height elongating my elbows making it harder for them to flex and absorb shock.

Later I was looking at the catalog page (for something unrelated to the seat post) for my bike and it said SR-CRE 100 Microadjusting 26.6 seat post.

Questions:
1) Could it be possible my bike really takes a 26.6? I'm assuming this is why I had so much trouble (when the other seat post would move freely around).
2) Could I purchase the 26.6 and use it in my bike? Will the tube now be overextended to fit a 26.6?
3) Did I permanently damage my steel double butted tubing? It doesn't look deformed and I never hammered to get it in, just twisted back and forth and stopped when it got too hot.

I would like to go to the 26.6 so that I can adjust further (sometimes even during rides) without having to swear profusely.

It doesn't have a clamp, it uses a bolt through the frame to secure the seat post.

Looks like this:
http://gallery.a-symmetric.com/main....serialNumber=2

Probably.

Too late now. If the seatpost was that hard to install, you should've tried the next size down. If that was extremely loose then you now have a problem.

Go ahead and try the 26.6 post. You got nothing to lose.

If you sanded the oversize seatpost down a bit, it probably didn't hurt anything when you did a bit of force fitting. If you get the correct diameter seatpost it will fit better but your frame is probably fine.

Usually a too high saddle causes knee problems due to leg hyperextension. I've never heard of elbow problems due to saddle height.

well, took it into licktons, and although they didn't have a 26.6 in stock, they used a 26.6 old post to try. Worked fine, no frame issues. Why would my old one say 26.8, oh well.

The reason I get the elbow pain is beacause my arms are overextended when reaching the drops. True, getting a little knee pain alsò but should have the new post by mid week so no worries.

Elbow pain is most likely due to straight-armed locked-elbow positioning. You'll want to always have your elbows bent to absorb road-shock. Really relieves shoulder and neck pains as well. Most common cause of the straight-arm position is having bars that are too low, not a saddle that's too high. Saddle-height should be adjusted for optimum leg positioning over the bottom-bracket.

i have a 26.6 bike, and when i originally tried to install a 26.8 post it went in fine...for the first few inches. after that it was really tough, so i figured i needed a size smaller.

perhaps your old seatpost is shorter than your new one?

This one went in fine for about an inch. Every indicator said 26.8, even measurements. Yes, the old seatpost is shorter, but after cutting the new seatpost down to about the same length, it still wouldn't fit. After they put in the 26.6 test post, it was just like the 26.8 (old one) I have, plenty of easy play, without any force required to get it up and down.

Can't wait for my new seatpost.

Seat posts are like spark plugs......there's WAY too many different ones out there.
Where the heck are the bean counters when you need them? Adopt ONE standard size, and everything would be so much easier!