Seat post slipping slippage

I have a 2011 Rumblefish II. Just slapped a Thomson Elite seat post on it and continue to have slippage. I've used the clamp collar that came with the bike... And recently bought a twenty6 clamp that I have gone to 7n.m on. And it slips. 2 plus inches. Any advice?

 

sharpie mark the post. The sharpie mark makes it easy to adjust back until you solve the slippage. I took off the QR and used a bolt, that fixed mine
Happy Trails

 

may not be what your looking for but this has always worked for me.
i apply a small amount of "toothpaste" on both seat (inside) tube and seat post (part that inserts to the frame)
just enough to do a lite coat on the metal.

 

Clean everything off PERFECTLY. I want it CLEANER than your rifle bore. Use acetone, lacquer thinner, alcohol, or any kind of solvent that isn't oily. Clean the seatpost and tube until a white rag comes out clean. If you're dealing with carbon, just use the alcohol, not the more aggressive solvents. You can use grease, but you have to use your finger and get it down into the seat tube and NOT on the clamping area. The clamping area has to be so clean that you'd eat off of it.

 

At the risk of sounding like "obvious guy" make sure the split in your seatpost clamp is on the same side as the split in your seat tube. I had a friend who was having chronic slippage until he finally realized that he accidentally put his seatpost clamp on backwards.

 

What everyone said above plus the following:
Take a 400-600 grit sand paper and roughen up the inside of the seat tube nearest to the clamping area.
Apply a thin layer of grease between the post clamp and the outside of the seat tube where it slips over.

 

If you don't drop your seatpost much, go with a non-QR. Fixed the problem for me.

 

Friction paste might do the trick. It helps with slippage and will prevent creaking as well.

 

Do you have the right seatpost diameter 31.6?

 

I'll give er a good clean. If i stick with the non QR... does anyone have suggestions on torque? I've gone up to 7 n.m. And yes i have the correct size post and clamps. The Thomson actually slides down snugger than the stock bontrager post.

 

Toothpaste works! A light coat did the trick. And it smells great! Colgate.

 

Not to mention your seatpost won't get cavities! Win win!

 

use a carbon paste or i think its called like fiber paste or something like that every bike shop should have it.

 

Lose some weight so there is not as much pressure on the post when sitting?

 

@emcil.... thanks for the help. I've only battled anorexia nervosa for the past 2 years so your comment is inspiring!

 

I just figured you had plenty of good answers but might be looking for one inane one. Wasn't meant to inspire anyone.