I’ve had an issue with my seatpost slipping for a while now. It’s a KCNC SC Pro Lite post in a Kinesis XC Pro 3 frame. The fit is very tight – I have to use force to get it in and out, so it’s not as though it’s too loose. I imagine that when I go over a bump and my ghetto booty hits back onto the saddle hard enough, it is forced down. I’m not exactly a fat b’stard, 83kg, so it probably shouldn’t be happening.

I was using a light KCNC seatclamp, which has been replaced with a slightly heavier duty no-brander, but the problem persists. Is there any way to remedy the situation?

My Marin did that. I cleaned out the grease inside the seat tube (oops) and used anti-slip stuff instead. With a wider tighter (QR) seat clamp it was fine.

My friend you need carbon assembly paste.

As above carbon assembly paste you will barely have to tighten the seatclamp.

http://www.wiggle.co.uk/ritchey-liquid-torque/

There’s enough in that sachet for several seatposts & bars

How about a double seatpost clamp?