To lube or not to lube.
 

Next week I will be assembling my new project bike and it will be the first time I've ever owned or used a carbon fiber frame. There seem to be disparate opinions on whether or not to grease carbon fiber. I'm concerned mostly about the fork and the seat post. The fork steerer is carbon fiber as is the frame. The seat post is aluminum. I'm not worried about the bottom bracket since the frame is lined with metal there so it will get greased normally. Thanks for any input.

Hmmmm. Surprised no one answered.

Trek says not to grease the seatpost in their OCLV bikes (well, mine said not to). This bike has a plain fiberglass liner where the seatpost contacts to prevent electrolytic corrosion that some early bikes had. If yours doesn't, grease might be good.

Can't help on the fork steerer.


Hope this helps.
Bob

Thanks, Bob. Perhaps there isn't much experience with CF on the forum. Electrolytic corrosion wouldn't be caused by carbon fiber since it isn't metal. I was just worried that grease and carbon fiber didn't go well together but there is no logical reason that should be the case. But, as to illogical reasons........

No grease required on the seatpost. Are you saying it's got a totally carbon head tube? I don't think I've ever seen that, didn't think it was possible. If it's aluminum it should be faced and greased before installing the cups just like your bottom bracket. Internal headsets can be lightly greased where bearings contact metal, but I'd keep grease off that steerer tube and any other carbon parts.

Edit: Do not face head tubes designed for integrated headsets, only ones designed for press fit cups. Should be common sense but I'll throw it out there just in case. :)

Grease has been known to penetrate and weaken carbon parts. It's just plastic, after all. :)

I've heard that grease to cf is like vaseline to condoms. It makes sense at the time but....

you never grease a carbon steerer beacuse it will slip. you grease metal on metal, the reason you grease it is so they dont bond, fuse, however you want to say it. if the seat tube grabber thing is metal and ur seat tube is metal then grease that ,otherwise dont bother

Well, you don't grease a (threadless) alloy steerer at the stem where slippage would occur, either. And what exactly would be the point of greasing a seatpost clamp? Alloy clamp against carbon seat tube against alloy seatpost. No metal on metal there, no grease.

Well, I know that when i'm trying to stick it in a tight spot, i'll always use lube. Or at least spit on my hands. Oh, we're talking about bicycle mechanics? :D

Do not apply grease to any CF. Over time, grease will break down the resins holding the fibers together, causing delamination.

As a followup, I'll post the result. The frame head tube is not lined with anything. It is bare carbon fiber with places machines for the bearing races to fit. The bearings are covered and lubricated inside the races. There is no need to lubricate one of these integrated headsets anywhere. In fact installing them couldn't be simpler. Just put the parts together, scribe the steerer, disassemble, cut the steerer, reassemble and tighten down the expanding part on the headset. Really simple. It took less than 10 minutes. The seat post, of course will need no lubrication either since it is carbon fiber against carbon fiber instead of metal to metal. Thanks for the advice. Everything went together with ease.

Just an FYI - carbon fiber can and does experience electrolytic corrosion. Anything that is a reasonable conductor of electricity does. Of course, you still don't need to grease it, according to your post...