I recently got myself a Yeti ARC and I’m really enjoying it apart from the saddle slip. The seatpost is a Thomsom elite, 27.2nm, with the seat post QR removed the seatpost is snug inside, there is no play or slop.

The slip is not much but it can be about 5-10mm during 20mins of climbing for example.

One option I’m considering is using some friction paste. I understand this is generally used for carbon components, but can also help seatpost slip on an alloy interface, any opinions?

Another option is to get a Thomson seatpost collar clamp which are supposed to be pretty good as they apply an even force around the whole tube, and much more secure than a standard QR

A beer can shim is another option.

Any suggestions would be helpful, it’s a pain in the ass to ride it as it is 🙁

Unfortunately Thomson posts often come up a little slim. Had it myself in a Whyte frame, different brand post fixed it for me after trying various other options like paste and seat clamp.

If the seatpost already seems like a “snug” fit, then by all means try some carbon paste. I tried the Tacx stuff and it’s cured the slipping issues I had ( alu post – steel frame )

There was a thread on here ages ago where the consensus seemed to be that some, particularly 27.2mm thomson posts were on the smaller side of what was still ‘acceptable’ tolerances, whereas some tubes were slightly on the larger side of that acceptable tolerance. I remember brant being involved in this discussion but i am not sure if this applied to on-ones. Also that somehow thomson posts being milled rather than forged/drawn makes a difference to them wearing a tiny bit more with repeated dirty-biked dropping/raising.
Fwiw i had a 2005 usa-made yeti that had such a good fit with the 27.2 raceface seatpost that when you pushed it in (there was no ‘dropping’ it!) you could hear air being forced out the headset!
Oh and salsa seatclamps rule!

paste is fine to use. I apply it to most things these days…

Ok, cheers guys, some interesting things to consider here

Have a look at the Exotic double clamp on Bikefridges site on ebay. It has one that clamps the post and the other that clamps the frame and has never slipped again on my dale.
eBay item number:

200723393294

Get rid of the Thomson post

^^ +1, I had problems with them creaking in Soul and RL853, changed to eastons and no creaks. All installed with fibergel.

Put a very small amount of grease on the post i.e. apply it and then wipe most of it off. Then cover it in sand/grit/dust before refitting.

I had a similar problem and the paste did not work for me.

I did use a double clamp seat collar and that really worked. The surly constrictor is another clamp that may work.