Speak to Gerrit!
For several years we have been using a plastic reducing sleeve (shim for short) on our idworx bicycles, which we glue into the seat tube of the frame. This shim combines several advantages in one component.
It effectively prevents corrosion between the seat post and the seat tube, which is normally achieved with grease. The surface of the seat post is protected from damage and it effectively eliminates cracking noises, as the seat post is inserted into the frame without any play.
Please do NOT use grease when inserting the seat post.
Firstly, it is not necessary for corrosion protection and secondly, the grease drastically reduces the friction between the seat post and the shim.
To prevent the seat post from sinking into the seat tube while riding, the seat clamp must be tightened with too much torque. In extreme cases, this can lead to damage to the frame.
