Bicycle Mechanics - Seatpost questions.

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cyclingshane73
05-29-04, 01:21 AM
Hey guys & gals.

I have been searching high and low for a carbon fiber seatpost to fit my 27.0 seat tube with little or no success. I have found a couple however not either a manufacturer I know or trust. That said, could I buy a 25.0 seatpost and shim it to fit the seat tube, or this a bad idea with carbon fiber seatposts? I thought I heard somewhere that this was a bad idea with carbon posts.

Secondly, is there any installation tips I should be aware of. I also believe I've heard that the seatpost and tube should be free of any grease on installation. Basically it goes in dry and lube free. Is this true?

Thanks in advance all.

khuon
05-29-04, 03:54 AM
That said, could I buy a 25.0 seatpost and shim it to fit the seat tube, or this a bad idea with carbon fiber seatposts? I thought I heard somewhere that this was a bad idea with carbon posts.

I've always been led to believe that it is not a good idea to use shims on CF posts.



Secondly, is there any installation tips I should be aware of. I also believe I've heard that the seatpost and tube should be free of any grease on installation. Basically it goes in dry and lube free. Is this true?

From everything I've heard and read, CF posts should not be greased. I have never greased any of mine.
cyclingshane73
05-29-04, 04:01 AM
I've always been led to believe that it is not a good idea to use shims on CF posts.




From everything I've heard and read, CF posts should not be greased. I have never greased any of mine.

Yep, thats what I thought. Thanks man.

Raiyn
05-29-04, 10:23 PM
From everything I've heard and read, CF posts should not be greased. I have never greased any of mine.Grease has the potential to cause a chemical failure in the carbon. But the main reason for greasing a post (or any non-moving metal to metal contact) is to prevent the parts from corroding together (ie galvanic orrosion). Carbon doesn't corrode so it's a moot point.
khuon
05-29-04, 10:49 PM
Carbon doesn't corrode so it's a moot point.

To add to that, carbon fibre components generally have a slippery enough laminate surface layer. Greasing that would make it even more slippery thus promoting over torquing of the clamp to keep it from sliding which can lead to crimping of the post and eventually structural failure.
Raiyn
05-29-04, 10:51 PM
To add to that, carbon fibre components generally have a slippery enough laminate surface layer. Greasing that would make it even more slippery thus promoting over torquing of the clamp to keep it from sliding which can lead to crimping of the post and eventually structural failure.Bonus points for you Bud!:beer: