Bicycle Mechanics - Grease carbon seat post in AL frame?

I would for sure if it was metal to metal but what about preventing corrosion in the AL frame and possibly binding the post?

No

No.

No as well. I think you're supposed to rough up the surface that goes into the seat tube to help it hold. Search the forum first though, before screwing up that cf post.

I grease mine. well, it came like that on my Specialized Sirrus. The seat stays on mine. If it doesn't, I guess you have to tighten up the allen screw and nut!

At least 4 of the plastic bikes in our shop had a light coat of grease on the post. It's just as important that you observe correct torque on the binder bolt. Regardless of what Sydney might say, you will need a torque wrench.

Grease/oil can cause CF to deteriorate.

thanks for the replies.
I think I'll pass on the lubing.

I grease mine. well, it came like that on my Specialized Sirrus. Shop monkeys do that even when they shouldn't.

Grease/oil can cause CF to deteriorate.

I think this is voodoo in a lot of cases, but I wouldn't automatically rule it out. The question of whether grease will penetrate the coating and expand the fibers (which will cause your bike to immediately burst into flames and send you off a 320984102 foot cliff), as well as the question of 'roughing up' the finish depends not on the carbon so much as the finish applied over it, which varies from maker to maker. This finish is usually plenty smooth enough to slide into the seat tube no problem...if not, hone it out...aluminum is cool with that. Grease often causes the surface to be too slippery unless the seatpost clamp is tightened past recommended torque, that's the most obvious reason for not greasing.

no, you dont grease a carbon stem. im not 100 percent sure why but i think its cos it makes it slippy and then you have to clamp it down harder which isnt good for carbon because it has a very specific torque spec. you normally grease metals so they dont bond together. hope this helps

I think this is voodoo in a lot of cases,

You think wrong.

You think wrong.

Better run out and tell all the people with those Look 585s and other carbon framesets sportin' carbon steerer tubes and head tubes that the end is nigh, 'cause we been putting light amounts of grease on their carbon for years with no such trouble. For as long as some of them have been in the field (not to mention local and regional peloton) and as many miles as they're sure to have they ought to be bursting into flames any minute now. :rolleyes:

Will it erode cheap carbon? Who knows? Maybe. I guess it's possible, but I've heard nothing but pseudo-science to back it up (the old Vaseline on a condom argument...Polylube isn't quite Vaseline and an epoxy matrix ain't exactly a thin latex barrier, ribbed for her...or his...pleasure), not to mention never actually seeing carbon specifically damaged by grease firsthand. When I see it, sure...okay, I'll bite. Maybe it's not voodoo. I generally keep the grease off the carbon just to be safe, and for other legitimate reasons (slippage, torgue spec) but at least for SOME applications it's perfectly fine.

There is a VeloNews article http://www.velonews.com/tech/report/articles/8835.0.html where they talked to several people at carbon seatpost manufacturers and the answer is a pretty definitive no on any lube.

There is a VeloNews article http://www.velonews.com/tech/report/articles/8835.0.html where they talked to several people at carbon seatpost manufacturers and the answer is a pretty definitive no on any lube.

But not a unanimous 'no', which raises the question: can at least *some* of the many resins and finishes on the market chemically withstand it? Bontrager is willing to go on the record and say 'yes' in the article you've cited yourself. Apparently it's not affecting our Look riders (at least on the steerer and head tubes), either. And once again, it doesn't change the fact that grease on carbon seatposts is a bad idea...just that it may not in every case be this cool, sciency-sounding babble about pH balances and molecular breakdown.

There is a VeloNews article http://www.velonews.com/tech/report/articles/8835.0.html where they talked to several people at carbon seatpost manufacturers and the answer is a pretty definitive no on any lube.Well, they obviouusly haven't got the word on the Voodoo.

Shop monkeys do that even when they shouldn't.


I checked around at the local shop, and the search yielded no monkeys. Of course, should you happen to visit that store, they'd have to adjust the count. Are you planning of retiring from your rubbish spouting soon?