Thompson says to grease only the threads of the bolts on seat rail clamp. They say not to put grease on the washers or under the head of the bolts. They specifically state not to use anti-sieze and are silent on carbon assembly paste. No grease on the post itself for a carbon frame. Torque spec is 6.8Nm for the Elite, 5.1Nm for the Masterpiece.

Reference https://www.bikethomson.com/wp-conte...0/PostInst.pdf

Something is assembled wrong if the saddle is sliding and tilting or the post is broken. I would take it all apart, degrease everything, inspect and reassemble if not damaged. Only a small amount of grease on the threads of the seat rail clamp bolts. Make sure the clamp is not bottomed out on the post because of too great an angle.

Could be the OP has oval rails on his saddle. The clamps on Thomson posts are made for round 7x7mm rails. They sell a special clamp for oval rails up to 7x10mm. https://www.bikethomson.com/product/...pset-7x7-rail/

[MENTION=183557]rpenmanparker[/MENTION], why do you say no grease ever and why do you recommend carbon assembly paste? I'm not trying to challenge but rather to learn. I've never had occasion to work with carbon assembly paste but have read about it and would really like to hear what you have to say.


-Tim-