Fred Smedley

Aluminum seatpost into a aluminum frame, do you use grease or not to prevent seizure?

MattP.

I do.

You just want to watch out for CF seatposts (dont grease) and seatposts going into, say Ti frames.

BostonFixed

Here's a simple rule: Grease all metal-to-metal contact.

Except chains. (use oil).

'nother

I get why you wouldn't grease CF seatposts but could you please explain why you would not grease a post going into a Ti frame (CF excepted)? That makes no sense to me.

seely

With CF, if it is greased, it will slip. With Ti, you use Ti prep and not grease.

nick burns

If you ever want to move that seatpost in the future, grease it before installation.

Rev.Chuck

You do grease a alloy post going into a ti frame or ti post going into alloy frame. But ti and alluminum really like each other. So much that they can gall and bond from a low friction contact so you need to use a prep just for Ti parts.

Craig Calfee, a maker of high end carbon tandems says it is ok to grease a carbon post if needed to keepit from sticking. Expeimenting with my own stuff, I have never had an issue greasing a carbon post other than some of the very slick finished early ones slipping a bit. I have had to get three people together to wrench a dry carbon post out of a frame and I have had to cut one out before(Bright side is that it is easy to cut a carbon post in two.)

fore

Not that simple, buddy.

According to your rule I should be greasing my steerer / stem interface? And my handlebar / stem interface?

No thanks.

You know, Campagnolo specifically states not to grease crank bolts. Or bottom bracket spindles. Greasing those two makes it very easy to overtorque one's cranks. Since they're square taper, they'll keep on going until the chainrings bottom out against the chainstay. Makes it a little hard to turn the pedals over when that's happening.

HillRider

That's interesting. Litespeed says plain grease is all you need for Al fittings in their Ti frames. My experience says they are right. My Al seatpost has spent 10 years and 65,000 miles in my Litespeed frame, being removed and regreased with Phil Grease once a year, and has shown no tendency to gall, seize or do anything unpleasant at all.

BTW, Ti Prep is just Cu-based automotive/industrial antiseize packaged in small tubes at absurd prices. See an auto parts store for much more for much less.

Rev.Chuck

Well. i was once dry fitting a screw(ti) into a alluminum stem. It seized. Since then I have always used anti seize compuond.
Tiprep is copper based and you can get copper based prep at a decent auto shop. There are other types of antisieze as well
Sure you can use something else and it will work but why not use the best. Did you know you can use vegetable oil in place of engine oil, not the best choice but it will work ok.
I have been a mechanic for twenty years and earned a decent amount of my income from "will work" Leave that post in there for several years without moving it, like most people do, ride it all kinds of weather and try to pull it out. Or be the guy with the really acidic sweat that does a hundred miles a week. Deal with a twenty or thirty really stuck posts a year and you might change your mind.

top506

After the job I had getting the stem and steerer apart on the badly stored Miyata I'm working on I intend to do just that with the replacement stem (had to cut the old one out).
Top

ivan_yulaev

Eh, I think the threads sucked or you cross threaded it.

I use grease on my BB shell and seatpost and have no trouble removing either from my Ti frame.

gm1230126

15 years ago somebody actually did the work and tests and decided that when it comes to seat posts you were better of with Phil Wood's Tenacious oil (heavier oil) than grease because when greasing a seatpost it actually required over tightening of the seat pin to get them snug. Evere since then I've used Phil oil on mine.

Rev.Chuck

For what it is worth, I was putting the screw in with my fingers.

Do what you like. You can often run through a red light without slowing or looking and not get hit. Let us all do that as well.

For the guy that maintains his own bike and maintains it well, there are lots of things to be got away with. Hell, you can put any post in dry if you remove it often enough. Use triflo on your wheel bearings if you check them and relube all the time. Run your brake levers so they contact the bar just after the pads grab, you get your maximum hand strength that way. You just need to adjust the pad clearance everyday.

OCP

Grease any metal:metal contact points. you need to put a barrier between the two or risk sizing them together.

mechBgon

Galling is ugly. I remember when our local Costco store got hold of some Cannondale mountain bikes. A guy brought one in because the aluminum post had galled in the frame. Well duh... the "assembler" at Costco didn't grease the seat tube or the seatpost. That one had to be sliced apart from the inside, and it cost the guy quite a bit in labor, plus the cost of a new post. All for lack of just one healthy smoodge of grease.

Nachoman

Good discussion. I'll take this all under submission.

Sheldon Brown

ABSOLUTELY POSITIVELY FOR SURE NO QUESTION ABOUT IT!!!

Fred Smedley

Thanks for your reply's. I think I'll put a light coat of lubriplate on it and check once in a while.

Now how about my Ti seatpost in Cromemoly frame. I think there is a lght coat of grease on it now and it seems to be doing fine. Would Ti prep be smarter in this application?

cascade168

RC, yours is the best post in this whole thread. I have two Ti frames and the scariest experience I have had was screwing in the bottle cage bolts! Yeh, stainless into Ti. They felt like they were going to gall with every turn of the screw. I was using grease and it just barely did the job. I since have re-done them with a copper-based anti seize paste and that works great. The point being that not every tap and die is the same and when you get to approaching an interference fit with dissimilar metals, you better be really careful - if it doesn't feel right, it might be time to back off and rethink what's going on.

Also, the manufacturer of my Ti frame told me specifically to grease my CF seat post. He said, not a lot, but just a thin coating. I am glad to see all of this b/s of "never grease CF posts" starting to be questioned. Three years later, my CF post is performing nicely, thank you. No slipping, no spontaneous combustion. His BB installation advice was to teflon tape the BB and then grease over that. That has worked great and I have started taping all of my BBs and have had great luck. Anyone who experiences creaking when pedalling should try this.

Brian

For titanium to titanium joints, I use ti-prep. Same with aluminium to titanium. Our couplers have a healthy coat of ti-prep on the threads. So do our seatposts and bottle cage bolts. But I'm pretty sure I used grease on the bottom brackets though. Titanium is quite happy to cold weld itself to dissimilar metals.

HillRider

I assume you are referring to S&S couplers. S&S recommends only one lube for their coupler threads and that's "DuPont Teflon Bearing Grease." Years ago, this stuff was sold in 18 gram syringes at incredibly high prices as a general bearing lube. It was a marketing failure and disappeared from LBS shelves. Nashbar had it on closeout a few years ago but that source is gone. Now the only source I know of is from S&S Machine themselves or one of the bike manufacturers that installs their couplings.

Brian

And therefore, we use a healthy coat of ti-prep on the threads of our couplers. I check them once in a while too. Loosen, tighten. Get to play with my titanium spanner.

sngltrackdufus

I never have greased seatposts. I usually clean seat tube out with what ever cleaner is at hand ,give light "crosshatch" type sanding cpl inches in depth in the seatpost tube,clean out debris with cleaner & move the post here & there.

royalflash

if I used grease on my Scott Sub 10 (Alu post and frame) the post will always slip- there is no way I can use grease with it