bikemike73 

I have a Campagnolo seat post that is barely too big. Maybe 1 or 2 sheets of paper for thickness to be made smaller

Or use a grinding wheel ?

Has anyone done this before ?

Any, and all help appreciated.

Thank you

masi61

Before you bring out the sandpaper, I would make sure I know where the out of spec part is located first.

A set of metric dial calipers is what I use to measure my parts to within 0.1mm dimension.

Start with the Campagnolo Seatpost. Measure it’s outer diameter with your calipers. If it is a 27.2, Campy quality control would rarely produce a part over this dimension. Anyway, take note of the listed size and the actual size and write that number down.

Next, measure the internal diameter of your frame with the caliper. Be sure to measure in the front to back and side to side axis. Write down the 2 numbers. Is this number consistent with what your manufacturer of the frame lists it as?

So now compare the outer seat post diameter with the internal seat tube diameter, are they close in the dimension? It would help if you shot a photo of your seat tube, with a close up of the slit up the backside of the tube, and a closeup of the collar or built in clamp bolt. Post up your findings back here before taking any sandpaper (or God forbid, a file) to your Campagnolo post.

2 sheets of paper too tight makes me think that you are using 0.2mm too large of a post or that the top of your seattube got pinched in slightly somehow. This is why it is fairly important that you describe the condition of this junction.

i recently went through a pretty intense process of having to sleeve my vintage titanium bike’s seat tube which measures at 30.0 mm, to snug up my Tom Ritchey 27.2 carbon fiber seatpost sufficiently that it did not creak. It was a surprisingly difficult issue to resolve. Along the way I managed to snap 2 Hope seat collar bolts and also go from a 30.0/27.2 aluminum sleeve to a 30.2/27.2 aluminum sleeve to finally using a U.S.E branded Delrin sleeve that I believe was 32.0/27.2. Getting this junction right is worth the effort.

Have you fitted other seat posts to this frame and achieved a better fit?

tomtomtom123

you could check if your seat tube uses shims. If it does, you could switch the shim to a thinner one.

bikemike73 

Thank you for the responses

There was a seat post 27.2 in there.

A suntour....it was snug in there.

The campy one is 27.2...which is correct to the frame.

I think if I widen the top by expanding where the binder bolt goes..AND clean the seat tube, I'll try that first.
If that doesn't work, then sanding and filing will commence.
I'm waiting though to bring it to my good friend at the bike shop Monday.
He will have some answers as well.

He has worked on my vintage bikes for years and always has had very good success.

Please keep the ideas coming

Much appreciated
Thank you

jbucky1

Clean it up, use a bit of force, if not maybe try a 27.0 seat tube

www.buckyrides.com

https://www.etsy.com/shop/Buckyrides

zacster

I had the same issue with my Kuota carbon frame. It also had a 30.0 seat tube and I tried a 27.2 post with a shim. It never would stay in place. I'd start out a ride with the seat at the height I wanted and it was always bottomed out when I got home. Some days I would feel it slip when I hit a bump or leaned on it a certain way when I stopped, other days it would just gradually slip down. I tried carbon paste, I tried a torque wrench, and it would just slip. I gave up and bought a used Kuota seatpost that was fit to spec and haven't had any further problems. The original Kuota post got stripped and wouldn't hold the saddle in place and my guess is that 10 years down the line my new/old post will do the same. I'm not too worried though, I'm 65 and hope to still be able to ride at 75!

Miele Man

I bought a used bike where the Campagnolo Triomphe seat-post was tight. I managed to get it out and then I polished it with wet/dry paper by cutting strips of the paper and then running it over the seat-post by looping the paper over the seat-post and then pulling on each end. Then I put some sandpaper around a dowel, pushed a bit of rag into the seat-tube and then sanded the inside of the seat-tube lightly. I put a bit of grease on the inside of the seat tube and the seat-post went in very easily.

I wouldn't try either filing or grinding a Campagnolo (or any decent quality) seat-post as it'd be extremely difficult to maintain the roundness of that seat-post.

Cheers

JohnDThompson 

Don't use a grinding wheel on aluminum; it will clog the wheel and may cause it to overheat and shatter. If you really want to modify the post, use sandpaper, or better yet, a lathe.

Rather than desecrating a nice Campagnolo seat post, measure to be sure you don't just have the wrong size. Sell the one you have to finance the one that fits.

Cyclist753

You just need to make sure there are no burrs at the edge of the seat tube. You can feel with your finger. If so then de-burr the seat tube entry. Use 400 grit with oil wrapped around a wood dowel. Do this with the frame inverted. Sizing Rods are handy but calipers work.

unterhausen

You need to find a telescoping hole gauge for the seat tube. Lightly reaming the seat tube might work.

bikemike73 

Thanks again for all the great ideas!!!

I think..as mentioned above......sandpaper in pieces around the tube will have success and is conservative enough not to do any real damage.

I also bought a round wire brush for the seat tube to clean out.
There was a lot of rust in there.
Again...thank you all.
We'll be working on it tomorrow afternoon and I'll let all know the results.

dedhed

dsbrantjr

Sizing rods are MUCH better because they are truly round. A rod or hole can be WAY out of round but measure a constant diameter with a caliper or hole gauge: Extreme example: https://en.wikipedia.org/wiki/Curve_of_constant_width

bikemike73 

UPDATE !!!!

And THANK YOU ALL for the great ideas!!

I ended up getting the correct size post. I thought it was a 27.2......it was actually a 27.0.

Slid in and fit perfect !!!


Again.......thank you all

much appreciated

Michael

San Rensho 

The Campy seat ;post is probably right on. If its a tight fit into the seat tube and you KNOW the seat tub is the right diameter for the post, ream out the seat tube until the the post slides in smoothly. Oil or grease the post, install, tighten and you're done.

San Rensho 

Ooops. Nevermind. I guess I should read all the posts before I respond.