Possible frame issue?

[User16625]

My seatpost seems to creak a hell of a lot. I know the creak is part of the seat post (or its associated adapter) because cleaning it all out shuts the creak up for a couple of rides. To try to eliminate the noise I have:

Cleaned the seatpost and adapter (sits in the seat tube and the seat post is inserted into this)
Cleaned and greased all bolts
Cleaned and greased saddle rails and clamp
Regreased seatpost adapter
Smeared seatpost itself with carbon fibre assembly compound (seat post is carbon fibre, everything else is aluminium)

However the creaking always comes back quite quickly and it really does my head in. The most effective solution I have found so far is to stuff a wet wipe between the seat post adapter and the seat tube. I dont remember having this trouble when it was new and I dont get this with my other bikes including my MTB of the same material. Any advice?

 

[Levo-Lon]

Id change the adaptor..if its a plastic one
Im assuming you have a smaller post? So using a shim to make it fit...
they can be a pain have a alloy shim for my 30.9 reverb and thats great in the 31.6 seat tube.

 

[I like Skol]

Throw the crappy carbon seatpost in the bin and buy a decent Ali post that is the right size for the frame WITHOUT an adaptor.

 

[User16625]

Id change the adaptor..if its a plastic one
Im assuming you have a smaller post? So using a shim to make it fit...
they can be a pain have a alloy shim for my 30.9 reverb and thats great in the 31.6 seat tube.

Throw the crappy carbon seatpost in the bin and buy a decent Ali post that is the right size for the frame WITHOUT an adaptor.

Its a metal adapter. Both the adapter and seatpost are the original hardware. TBH I never regarded these sort of parts as things I would upgrade or replace. Seats that come with bikes have been good enough for me so never really gave them or the posts a second thought.

 

[JMAG]

Throw the crappy carbon seatpost in the bin and buy a decent Ali post that is the right size for the frame WITHOUT an adaptor.

I've just ordered a seatpost adapter so I can chuck away the crappy, stiff, ali 31.6 mm seatpost and get a decent, more compliant, carbon 27.2 mm seatpost!

 

[Citius]

I've just ordered a seatpost adapter so I can chuck away the crappy, stiff, ali 31.6 mm seatpost and get a decent, more compliant, carbon 27.2 mm seatpost!

You might end up disappointed then...

To the OP - my guess is it creaks because of the size differential on the parts of the post that aren't covered by the shim. As someone suggested, buy a post of the appropriate size to match the frame and see if that helps.

 

[JMAG]

You might end up disappointed then...

Only one way to find out. It'll work for some and not for others, so neither option is right for everyone. That was pretty much my point.

 

[Citius]

It won't be more compliant though. That was my point.

 

[User16625]

You might end up disappointed then...

To the OP - my guess is it creaks because of the size differential on the parts of the post that aren't covered by the shim. As someone suggested, buy a post of the appropriate size to match the frame and see if that helps.

Seems like the only option left. I just done a search and other Giant bicycles (my one in question is an SCR) that have the shim, have complaints of this problem. I also dont have this problem with my other bikes, but they dont have a shim for the seat post. Strange how a lube and clean seem to work temporarily tho.

 

[Citius]

Strange how a lube and clean seem to work temporarily tho.

Not really. Lubing and cleaning is always a temporary solution in any situation. Lube always runs out, and 'clean' always gets dirty..

 

[Andy_R]

sooo....you have to use a shim for the seat post you have and the seat post tube. And there is noise. And it is corrected (temporarily) by adding lots of lube. Ermmmm........get the right size seat post for the tube it's going to live in......problem sorted.

Just cos bike manufacturers/retailers sell you stuff, doesn't mean it's always correct....

 

[Illaveago]

What is your frame made of?

 

[Fab Foodie]

Seems like the only option left. I just done a search and other Giant bicycles (my one in question is an SCR) that have the shim, have complaints of this problem. I also dont have this problem with my other bikes, but they dont have a shim for the seat post. Strange how a lube and clean seem to work temporarily tho.

Ha! Has guessed it was an SCR before getting to this post, they were notorious for this.
I had a Aluminium TCR from 2004 with a rubber shim and that was always silent.
I also recall some using a short length of old inner-tube to sleeve the post and cover-over the joint so that the grease and lube didn't get washed out or dirt get in so readily.

 

[JMAG]

It won't be more compliant though. That was my point.

Surely that depends on the 31.6mm ali post I have currently and the 27.2mm post I replace it with? Unless you're saying that all thicker ali posts are equally compliant than thinner carbon posts?

 

[Citius]

Surely that depends on the 31.6mm ali post I have currently and the 27.2mm post I replace it with? Unless you're saying that all thicker ali posts are equally compliant than thinner carbon posts?

I'm saying that seatposts aren't really 'compliant' in any meaningful sense - regardless of material. The exceptions are things like the coblr or whatever it's called, or suspension seatposts, obviously, which are designed to actually move.