Carbon seat post bonding - prevention?

[BdaGhisallo]

Is there anything I could do to prevent a carbon seat post bonding itself in my alu frame? Absent grease (which I'm sure will let the post slide down into the frame) and regular post removal and cleaning and such, is there any kind of substance or treatment I could apply to render this possibility moot?

The post I am considering is a PMP carbon post. I have the ti version and like it a lot, but I am jonesing for a black post. I know, pure posing is leading to this dilemma, but we need something to excite us, right?

Many thanks.

[jartzt]

Grease tends to break down the resin on the post and make it MORE likely to bond into the frame. Clean the seat tube and the post carefully prior to insertion. Periodically take it out of the frame and clean both. Follow this and you should be fine. Interested in what others have to say as well.

[sspielman]

If you grease a carbon post, it is doubtful that you will be able to secure the post enough to keep it from slipping without exceeding the torque recommendation and cracking the post. I'll echo the earlier comments and say that the post and seattube should be clean and smooth and that the post should be periodically removed for cleaning....especially if sweat has had a chance to get on the interface. Also, take great care in securing the post to the recommended torque (use a torque wrench!) and use a Campagnolo seat collar or turn the regular seat collar backward to avoid concentarting the stress at the seattube slot. Following these recommendations, a good carbon seatpost should last several times as long as the fork of one of the 7 most fabulous bikes of all time-past, present and future..

[BdaGhisallo]

Thanks for the feedback. Your suggestions sound like the simplest way to go. I do have a campy clamp on there now, with my ti post. The recommended torque for the clamp, 10nm as per campy direction, is simply amazing. I tightened it as far as I risked using a hand allen key and then checked it using a torque wrench and I was barely at 7 nm!!! If they think 10 nm is okay for their carbon posts, which are some of the more fragile ones and most susceptible to clamping forces ( hence their development of their clamp), then any other good post should be no problem at all!

Thanks.

[Richard]

A bit of information for those who don't use the Campy Clamp on a carbon post. Yes you should turn the clamp around, but you should also take a half-round file and lightly chamfer the split in the down tube at the top of the tube. This will insure a good tight fit without damage by relieving any crimp that might occur at the sharp edge of the split.

[Too Tall]

OUTSTANDING Richard :)

[Matt Barkley]

I use a little grease when necessary. (Nice red synthetic grease - barely a wiped off smudge.) Sorry guys. It has been the only solution I have found many times - now going on 6 years. I also hate the way a reversed clamp looks. I just run them to normal direction. Of course this is with good quality carbon posts - larger than 27.2 diameter most of the time. When I have and can use a campy clamp I will. I like when builders make a seatpost clamp part of the frame as opposed to slapping on a seatpost clamp - especially the really cheap ones. (I am sure they do this to prevent consumers from overtightening and cracking seatposts - usually the clamp will strip-put first) As for torque wrenches - which I have several - sometimes you gotta tighten a bolt so whatever you are tightening doesn't slip. Sorry if this made some of you uncomfortable. I know it made me uncomfortable. :beer: - Matt

sspeilman's advice for regularly removing and cleaning the post is the best advice IMHO.

(Oh, yes, sorry - the seatubes aformentioned have been either reamed, and or ball-burnashed sp.?)

[Too Tall]

You mean Flex Honed yah? Coat it with earl.

[zap]

No grease. Regular removal.

[davep]

I have a Fina Estampa and the only way I could adjust the carbon seatpost was by putting a little grease on it. No slipping.

[Matt Barkley]

TT - Flex Honed. Wow, maybe I should start drinking coffee... I only fear that it won't help any... :) - Matt